Linux, much like candy, comes in many flavors. This might be a bit overwhelming, like going to the grocery store and seeing 50 types of bread. Sure, they're all essentially the same thing at the core, but there are a lot of additions. Some are very basic, the white bread distros, and others are hearty and jam packed with nuts and other nuggets, the full service everything you could need and then some distros. There are some that come ready to eat, some need cut, and some even need baked and are just the ingredients (I'm looking at you Gentoo). What follows is the epic tale of my search for a Linux for all seasons. This is by no means an exhaustive list, but a list of what I've found to be the best for a few different categories.
As anyone familiar with Linux knows it's similar to a bag of jelly beans, there are a lot of flavors and to find the one you like best you need to do some serious taste testing. Any of our regular readers may have guessed that my top pick currently is Xubuntu. It is now in version 8.04, and for more information you can read our other review on the current release. If you like Xubuntu you can try the other members of the Ubuntu family: Ubuntu, Kubuntu, Gobuntu, and Edubuntu. They're all fairly similar, and all worth trying, but Xubuntu uses XFCE and is the lightest and most versitale of them.
JeremyW: SUSE (openSUSE) was my first true Linux love before I met Xubuntu. Don't get me wrong, SUSE is still great, but now-a-days I'm a big fan of lean and mean, yet still powerful distros. Just before I started writing this, I got an email that openSUSE 11.0 is out now, but 10.3 is still the download that you are pointed to on the openSUSE page. I think this is done to give early access to people who support the openSUSE project by paying for their CDs. openSUSE comes in two main flavors now, one that uses Gnome, and the other KDE. If I'm going to run a resource hungry distro, I prefer to run KDE, but either Gnome or KDE will work great for you. openSUSE is really easy to set up and use, and has great hardware support and auto-detection. I would suggest getting a Live CD of one of the two versions to try it first, but I think you'll be pleased. KDE 4 (which is included with 11.0) tilts the meter on the eye candy scale too with the addition of the Oxygen icon set among other things. I'm also a big fan of the way that the applications menu has been done in the later 3.5.x versions and in 4.x. The repositories for openSUSE are very complete, so you'll find most of what you need through YaST2, SUSE's package manager. All this, and the technology of Novell's pay-for offerings trickling down to this open version, who could ask for anything more (other than Novell not having a partnership with Microsoft)? So, if you have a 1.4 GHz Pentium 4 (or equivalent) or higher, 256 MB of RAM (512 recommended), and some time, I would recommend giving openSUSE 10.3 (or 11.0 if you wait a few weeks) a try.
Fedora 9 is a free Red Hat version released May 13, 2008; which should mean excellent tech support and community support. Typically I would say it would be an excellent choice. I'm not sure if it was just my hardware, but I found it to be a nightmare. I set up all these distros on separate partitions on my 3.2GHz dual core P4 with 2GB DDR and an ATI Radeon 9800 Pro, and all ran blazingly fast. Fedora 9 however refused to configure Xorg correctly, and was the only one to have problems. Once I got that sorted out, I found out that when Fedora installed GRUB to my MBR it refused to let me boot any OS but it and I couldn't install over it from any other OS for some reason. I had to erase my MBR and reinstall from a Xubuntu CD. I recommend that if you want to try Fedora 9, don't do so if you plan to have any other OS installed. They claim Fedora 9 is the first non-destructive USB installable distro (Puppy Linux has been USB installable for years, though they may be splitting hairs on definitions here), the first major distro with KDE 4 by default (which isn't true because Kubuntu-KDE4 came out in April), and state "Fedora is the first to deliver, and while we're happy people reuse the open source goodness we provide, we want people to know who's behind it." While Fedora is an OK distro, their attitude and major flaws prevent me from recommending them for general use, and I expect to receive hatemail for that.
Gentoo, barely a step above Linux From Scratch, in terms of both control and difficulty of setup. If you want to learn all the under the hood basics and have full control of your OS I recommend starting with LFS and using Gentoo only if you're a masochist. I realize, I'm going to get hate mail for that one, but for most uses Gentoo is overly complicated. While not easy to setup, these are both extremely powerful distros and can be tweaked to exactly the way you want them, and I guarantee that after using either one you will have a true appreciation for a prebuilt operating system and all it can do.
Live distributions run the full gamut from bloated behemoths to super simplistic and speedy. For general use I prefer Puppy Linux or one of its derivatives. They just recently released Version 4.0 "Dingo." If you need something even smaller or more specialized you can try one of their community developed Puplets, which are Puppy derivatives. Puppy itself is only 80MB, making it rival another small live distribution I will talk about in a bit, DSL. It can be booted from a CD or USB drive but can also be installed alongside another OS. In spite of its size it comes with productivity software, multimedia software, and a very easy to use interface. I discovered it last summer and fell in love with it, it's extremely easy to customize and remaster and I've used it mainly for recovering broken systems and wiping hard drives. It uses the JWM window manager and has a specialized package manager called PupGet. Most of the programs you will want are right on the desktop, where they're easy to find. You're running in the root environment, so anything you do in the terminal will have full root permissions, no messing with sudo. It installs customized packages saved as .pup files. JeremyW has some experience making these as Puppy was the base for the Wireless Thin Clients post.
The next tiny live distribution I've had some luck with is Dang Small Linux (The PG name anyway), or DSL. DSL I like for its size, but not its appearance. It is 50MB and fits nicely on a miniCD. It is currently in version 4.2.5, which came out in January of 2008. You can choose to use JWM or the very tiny FluxBox window managers. Now FluxBox may not be pretty, but it does run on a 486 better than anything else I've seen. They also provide virtual machine images and an embedded version, meant to run within Windows, which gives it a niche market. Much like Puppy it comes with some very basic text editors, spreadsheet software, browsers, and other useful software.
If you want a live distribution with all the horsepower of an installed system then you should give Knoppix a try. It will remind you a lot of the Desktop versions of Ubuntu and its derivatives, and is also a Debian relative. Unlike the previous 2 distros I've talked about here Knoppix uses KDE as its window manager. It comes with OpenOffice.org, which may cause you to scratch your head. You may ask, "How can an OS small enough to fit on a CD hold such a large software package?" It's simple, Knoppix uses a boot loader that decompresses an image which is loaded into RAM, an image that can be up to 2GB for a CD and 8GB for a DVD.
The only distro I've come across that is specifically designed for education is Edubuntu. You Maxwell Smarts out there may have figured out that Edubuntu is a member of the Ubuntu family, and with 8.04 that's become even more obvious. Edubuntu now has to be coinstalled with Ubuntu to function. After installing Ubuntu you can install Edubuntu which adds the educational packages and makes some GUI tweaks. I did some testing with my parents, both teachers, and got their reactions. My mom, a first grade teacher, said the software was great for them and would work great. My dad, a high school chemistry teacher, didn't like most of the science software provided in the repository, but there is a lot of software out there to try. I would say Edubuntu is mainly usable in an Elementary School setting, but I still hesitate to recommend it because it uses Gnome and has higher hardware requirements. The software available with Edubuntu is all in the Canonical repository, so it can be installed in Xubuntu which will run much quicker and on older hardware.
The first Linux server distro I want to cover is CentOS. Many of you may not have heard of this, but I really like it, especially for hardware support and setup. The fileserver at the facility I contract for recently succumbed to the capacitor flaw, and so I had to make a quick change. JeremyW had originally set the server up with CentOS and it worked very nicely. I took the RAID controller and hard drives and put them in another computer, and upon startup a configuration utility ran that removed the old hardware profiles and reconfigured the new ones, so with no trouble for me beyond a few keystrokes the server was up and running again. It is based on Red Hat Enterprise Linux, and is currently in version 5.1. RHEL is a commercial product and on the cutting edge, but for most small businesses and home setups CentOS is a great free (as in beer and speech) alternative.
For a somewhat more secure server, because it lacks a graphical X server, you can try Ubuntu Server. It comes with the same great support and community as the rest of the Ubuntu family. If you're familiar with a normal Ubuntu text-based installer there's really nothing new to explain here, and if you're familiar with using the terminal you will have no trouble with Ubuntu Server. I haven't had a lot of time to do much with this, but I will have a separate post on Ubuntu Server in the future.
I've been working on cluster computing for a few years now, and just in the past year found what I consider the easiest HPC OS distro to set up and use. PelicanHPC, previously the Parallel Knoppix project, is designed to run on a single computer acting as a master server that hands out boot images to the nodes, which are required to have PXE enabled network cards. For more information on that see our upcoming Cluster Computing Post (I'll add the link when it's officially up, watch for the update). The nodes for the cluster need at least 128MB RAM, which may require updating some older computers, and really need only the motherboard (with processor and RAM of course), a PXE enabled NIC, and a power source. Simply start the server computer with the PelicanHPC CD and follow the directions in their cluster setup wizard.
Hopefully you have found at least one new distro to try, and if you have another one or more to add please comment and give us all some more information.
Linux From Scratch
Red Hat Enterprise Linux
Linux Journal: Almost 9 Distros in Almost 6 Minutes