btmiller is spot on. and you'll find knoppix available here
Another luxury of knoppix is that you can install it to hard drive (if you've got the space) and because it's debian based, you can get updates/new or different packages with the excellent "apt-get" tool (once it's on hard drive).
Plus, not forgetting that knoppix has some of the best hardware detection available.
As per usual, the only possible snag might be modem's (it should do the graphic's ok) i.e. if you use dial up, then you might find it a challenge getting the modem working, if it's a "winmodem". But for that, you'd have to check here
Hope that helps some.