Aqua-Soft ForumsUbuntu is awesome.
[help] which linux
im assuming your new to linux.. did you even tell the X server (GUI) to run the Nvidia drivers? Im not sure if ubuntu has a package management where you can download the Nvidia drivers and it ocnfigures it.. but just installing the drivers iwll do nothing. You probebly havnt told X to use the new drivers, so it may still be using the old default vga drivers.
Also, Knoppix is an Excellent top notch Distro to use for a Live CD, I recommend it!
-Bolero
I've been using Mandrake since like 3 years, and it's in my opinion one of the best...Ubuntu is nice too 
I don't have any right now as for some reason Ubuntu's newest version won't install. I had Mandriva LE 2005 for a while, but for some reason it kept on dying. Plus my POS Winmodem won't work in any of them so far. Its supposed to work under Ubuntu 5.04 but I can't get it to boot even from the Live CD right now, something about unable to initialize the shell and unable to continue the installation.
I'm going to try Ubuntu soon. People say the SUSE Linux is also good enough. My boss uses RedHat on his laptop (but he works mostly in Windows XP 
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Just for fun, I'll go out of my way and suggest you take a look at Arch linux. www.archlinux.org
Not quite as daunting as Gentoo, but still decently low-level and helps you learn; plus it starts from a very base system and you install/upgrade from that.
Going through a bit of a growing-pain from 0.7 to 0.7.1 to 0.8 though - make sure you get the 0.7.1 ISO if you're gonna give it a try, lots has changed.
My Ubuntu arrived at last. Installed and tried it yesterday. What would I say? Woooooow! I didn't expect such powerful desktop OS out of Linux. This is very nice, tho it still smells a little geeky and programmer-oriented OS. But at least I could customize it to my beloved style very fast (remember, I'm using my first ever linux!). I could do some system adjustments, walked through the hardware configuration and so on. Very nice system. I didn't expect so much power.
i suggest once you've enjoyed a few days/weeks/months/years of this power (and gained some good and bad experience), you might want to move over to a source based distro.
and for those already looking at a purely source based distro, though gentoo may be the first word (why not, it has an amazing user base), you may also want to try SourceMage Gnu/Linux
it's fast (even if its not fully optimized), sorcery is written in bash (!), and the dependency system is very well handled (no multiple version confusion). its still pre-1.0 but i've had minimal problems using it (been on SMGL since 2004, still guilty of using win xp a lot though). almost any program you'd want is there as a spell. if it isn't you can always make a request.
read the faq on the website for more info.
Glad that you enjoyed Ubuntu.
Gnoppix stabel edition based on unbuntu and really good for begginners