I am a real fan of SimplyMepis (3.3.1 is current). It is Debian based and includes all the kewl toys one would need for a FULLY functioning desktop linux environment. It also has a nice easy installer if you decide to go that route. Consider this one a complete solution, but having said that, the download will be larger (650MB or so). Mepis features KDE as your window manager.
I also like the Ubuntu family, primarily because they are a little ahead of Debian core, whereas Mepis likes to be right in line with Debian releases (Debian is not known for speedy releases/updates). Ubuntu itself features X.org for Xwindows which is positioning itself to replace XFreee86. In the long run, X.org will outperform XFree IMHO. I don't use Ubuntu as I'm not a huge fan of Gnome simply because there is not enough customization available. That will change in the future I'm sure. The default setup does look VERY nice however. I use Kubuntu from this family, which is basically the same distro, but using KDE (3.4 currently). KDE has lots of bells and whistles and tweaks, but some will argue that it is alittle bloated and slower. It boils down to your own personal opinions. The Ubuntu distro is missing a few items that Mepis is not, but if you are sticking with live cd only, this should not slow you down.
We can't forget the grand daddy: Knoppix. Another Debian based distro, live cd, lots of stuff.
Best of luck and lemme know if I can be of more assistance!
Be well, SD
Edited by SoccerDad, 26 July 2005 - 11:39 AM.