For enterprise servers, the choices are (basically) easy: Red Hat Enterprise Linux, SUSE Linux Enterprise, or Ubuntu Server – all very good environments with good support from their companies and supported by various hardware manufacturers. What about your desktop?
The choice is usually easy: most of us choose one of the common distributions – like Fedora, OpenSUSE, Ubuntu, Debian, or Linux Mint. What if you want to stretch a little – try something more avant-garde?
You must define your boundaries – what do you want to have or to accomplish? Here are some possibilities:
- Do you want to build the software from source?
- Do you want extensive packages already built?
- Do you want to start from a minimal system and build up?
- Do you want run on old or minimal hardware?
- Do you want stable releases or a rolling release?
- Do you want a full-featured desktop?
- Do you want to run Linux?
- Do you want to run Flash, MP3, DVDs, etc.?
- Do you want to configure everything yourself?
- Do you want to build everything yourself?
- Do you want a special purpose distribution (e.g., penetration testing, multimedia, scientific, etc.)?
I find myself in the situation of trying to fix some hardware which requires installation of a new system – thus, I thought I would try something new. My criteria are:
- Support for lots of packages
- Everything mostly works on install
- Window manager other than GNOME or KDE
- Good security
- Good support for Java, DVD, MP3, and Flash
- Not mainstream
- Actively supported and with active community
So far, the choices seem to be:
Almost all of these are based on Debian unstable or testing; Sabayon is based on Gentoo, and LFS is based on nothing at all…
I’ve always wanted to try a Linux that had the equivalent of FreeBSD’s ports tree…
UNIX Administratosphere 
+1 for aptosid. Im using it for 2 years without any problems.
Can I point you at Funtoo. Its a Gentoo derivative. The main difference from Gentoo are a git based portage tree (instead of rsync) and some built in overlays. Unlike Sabayon you will have build your own kernel and that it doesn’t come with an automatic installer.
Do you want to build the software from source?
Some Linux distributions, or the BSDs
Do you want extensive packages already built?
Some Linux distributions, or the BSDs
Do you want to start from a minimal system and build up?
Few linux distributions, or the BSDs (FreeBSD vs PC-BSD)
Do you want run on old or minimal hardware?
Only the BSDs
Do you want stable releases or a rolling release?
Stable Release – BSDs.
Rolling Release – Linux (some distributions fake it)
Do you want a full-featured desktop?
Some Linux distributions, or PC-BSD
Do you want to run Linux?
Not if you have ever looked at the Linux source code 😉
Do you want to run Flash, MP3, DVDs, etc.?
Some Linux distributions, or the BSDs
Do you want to configure everything yourself?
If yes – Linux; If no – the BSDs
Do you want to build everything yourself?
See above
Do you want a special purpose distribution (e.g., penetration testing, multimedia, scientific, etc.)?
Linux tends to win here.
Do you want run on old or minimal hardware?
Not only BSD, do not forget about Slackware. Besides, why you folks saying about BSD think Free? OBSD rules! 😉
Support for lots of packages – FreeBSD has 23,000 ports and packages
Everything mostly works on install – PC-BSD has it there for you
Window manager other than GNOME or KDE – Your choice of DE or WM
Good security – Only the BSDs
Good support for Java, DVD, MP3, and Flash – FreeBSD or PC-BSD
Not mainstream – silly requirement, but the BSDs win here
Actively supported and with active community – Linux or BSDs
I love BSD (although I’ve never tried NetBSD) – but there is two major hiccups with BSD. One: the number one distribution, FreeBSD, doesn’t come with a fully complete desktop on install; and two: applications that everyone requires don’t work without a Linux-emulation layer (e.g., Flash, Netscape, others). Now, FreeBSD can be made to have a full desktop (with power management, hibernation, sleep, graphical startup, power saving, etc.) but it isn’t designed for it (although PC-BSD is). I know: I set up a full FreeBSD desktop once upon a time: lots of work.
For BSD, I’d really like to see it have native support for Flash, and no Linux emulation layer needed for any applications. Will it happen?
The “non-mainstream” requirement falls under “I want to try something new…”
Oh: one more problem with BSD: updating the core system is a major headache including a complete system rebuild. I’m sure it’s gotten better, but all of the Linux variants that use packages (and UNIX too!) put the core system into packages. Why not put the core BSD system into the ports tree? Getting an updated _mount_ or _cd_ or _ifconfig_ shouldn’t require a special process.
I’ve always wanted to try a Linux that had the equivalent of FreeBSD’s ports tree…
Gentoo portage?
I used #! for about 18 months, until about a year ago… It was a pleasant light-weight distro.
Maybe someone will help the Linux Distribution Chooser[1].
[1] http://www.zegeniestudios.net/ldc/
Why would one want Ubuntu Server if he can get Debian?
Lots of reasons: the number one reason that comes to mind is commercial support. Several others: Launchpad, external PPAs, faster development, and things like Landscape.