Here are my recommendations:
MANDRIVA 2008 ONE (GNOME EDITION) (256MB RAM min req)
Best wifi support I've ever seen in a Linux distro- by FAR! Mandriva has its own wifi tool which has worked with every chipset I've tried with it yet, WPA and WEP. Compiz Fusion for Vista-destroying desktop FX, NV/Ati 3D drivers, MP3, Flash and MP4 playback all included on this live CD. Mandriva has a great control panel which is faster than YasT (SUSEs rival effort which both Debian and Ubuntu lack a decent equivalent of yet). I'd say this is the best disc for Linux noobs in most cases.
Ubuntu 7.10
If you actually turn off your machines and you're bothered about boot and shut down time like me- Ubuntu 7.10 is a good bet as it boots a full 30s faster than say Mandriva or Suse on my machine! Ubuntu(studio) is also quite special in that it easily allows me to have both a rt kernel and Compiz/Nvidia driver at the same time- installing the rt kernel under Mandriva 2008 messes the system good and proper unfortunately.
The best thing about Ubuntu is it its easy access to 22k+ reasonably uptodate packages through the wonderful APT packager. I would say that if you don't need the super-easy wifi support and control panel of Mandriva then try Ubuntu Alternate first. Ubuntu 7.10 desktop CD is OK for checking a system out but don't install off it- hasn't worked once for me and I tried it a few times.
If you want Ubuntu 7.10 with multimedia stuff included plus additional tweaks then try Mint Linux -
http://linuxmint.com/CPX-mini
This is my fave distro for the rebirth of machines otherwise considered useless- PCs with as little as 64MB RAM suddenly become lightning fast Debian boxes thanks to cpx-mini, a fluxbox/rox based desktop with auto-mounting of discs that can be installed on a 256MB usb stick!
http://debian.tu-bs.de/project/cpx-mini/The cpx-mini dev promises a sidux vased version will be out soon but an alternative to cpx-mini, if you can get it to work, is fluxbuntu which uses the same wm/file manager (fluxbox/rox) combo but has a much more up-to-date Ubunbtu 7.10 base. I've tried the x86 RC but failed to get it to boot tho.
2008 will be a VERY exciting year for Linux, without a doubt! Craiginator for one...
