I have a friend who wrote a utility for installing nvidia drivers on Debian based distros. Since Ubuntu is a bit different than most Debian distros, I'm trying to find out if it would work for Ubuntu 10.10. It not only installs, but, if your install is borked, it cleans up everything and does the reinstall automatically. I'm waiting to get work back. Hopefully you've found the problem, but if you haven't, I'll get back when I hear whether it works or not.

If you still haven't reinstalled, I've been told that the "sgfxi" script works with Ubuntu. If you borked your installation, and need to clean up the mess before reinstalling the nVidia drivers, this script can help. Link to manual page:
http://smxi.org/docs/sgfxi-manual.htm
The author won a Distrowatch award for one of his other scripts, so, you can trust his site and scripts. He's very much involved helping users maintain their Debian based distros, and, I've been following his work for years since my days with Debian Sid. He even modified his info script called "inxi" so it would work with my Fedora install. His inxi script also comes by default with distros like LMDE and a host of others.
If your still looking to fix your install and want someone to hold your hand, let me know. I can probably talk you through it right here in the forum. It's easy to install and run. Let me know if you still need help.

Tom