Personally, I always install the latest nVidia drivers by hand. What I'd suggest is the following:
1. Go to the nVidia driver download page
and download the latest Linux driver file. As of today, that's 8178. Note: I'm assuming you still have internet access; if not, use a Live CD such as Knoppix
2. From a terminal session, become root and install the driver. The nVidia page contains instructions on how to do this, but it basically is a simple
A plain text installation procedure will fire up, and the first question it will ask you is to accept the license agreement. Basically you want to just answer "Yes" or "OK" to whatever prompts you get. If you get a message saying that a previous version was detected, remove it
3. During the installation, you might see a warning message or two about the kernel modules, and again just answer "OK" or "Yes" to keep going. If all goes well, it will finish (I'd estimate that it takes about 2 minutes, give or take) and you'll be dropped back out to the prompt.
4. Once it's done, exit root, become your normal user, then startx
That said, and assuming you are familiar with how an xorg.conf file looks (which is what controls your X graphical environment) may still need to manually adjust that file if you still get an error. In my experience, the two most common issues that can prevent X from starting are improper vertical or horizontal sync rates, or that the wrong video driver is specified. For your card, you want the driver to be "nvidia". In any case, let's cross that bridge when we come to it. Good luck with it