As usual, the official Debian wiki has a great writeup on getting the Drivers installed. http://wiki.debian.org/NvidiaGraphicsDrivers. Do yourself a favor and read the document. It will give you the full story and not just the regurgitated short version below. I use debian because I like the packaging system. I think it works well. why add the agony of recompiling drivers whenever you update kernels and whatnot. Since X was broken, The key was to switch to a console session BEFORE logging in using GDM. As soon as the login page comes up, press CTRL+ALT+F2. This is what I had to be able to log in and use my X session:

Login as root.

I used the netinst disk and had to add the “non-free” and “contrib” repositories. to do this, edit /etc/apt/sources.list.

nano /etc/apt/sources.list

Find the line line that has something like

deb http://mirror.cc.columbia.edu/pub/linux/debian/debian/ lenny main
deb-src http://mirror.cc.columbia.edu/pub/linux/debian/debian/ lenny main

add “contrib non-free” to the end of both of these lines and then do a “aptitude update”

# apt-get install module-assistant nvidia-kernel-common
# m-a auto-install nvidia-kernel${VERSION}-source
# apt-get install nvidia-glx${VERSION}

In the device section, add

Driver "nvidia"

Restart GDM (and subsequently X)

# invoke-rc.d gdm restart

Install The nvidia settings interface thingy if you want. This can also verify if the driver is actually running.

aptitude install nvidia-settings

In debian, the package doesn’t install a shortcut for some reason, so just launch it by typing “nvidia-settings” into the console.

So your Ext3 root partition is corrupted. No matter how you try to log into your system, your system asks you for root password. But you are a good, obedient ubuntu user. And you do not have a root password set. You can press CTRL+D, but that just reboots. Are you boned?

No. problem. press ctrl+alt+delete. You will get a messy screen about having trouble launching your X session, but you will get a login towards the bottom of the screen. So just use your normal user login and password. after that, I use
sudo su