To get it back to how it was:
On the line that says:
change it to:
I believe this to be one of the downfalls of Fedora 10.
The file xorg.conf (the file that the X server gets all of its configuration information from) in a default installation of Fedora 10 is non-existent. Without having a properly set up xorg.conf, the nvidia driver is not able to write the whole thing either. I could be wrong about this but install Fedora 9 and you will see what I mean. If 3d acceleration is not a major concern of yours than maybe someone else can explain to you how to edit xorg.conf just to get the desired resolution with only the nv driver. I have done it but its been a long time and I have simply forgotten how.
What I would suggest is to install Mandriva 2009.0, they don't suffer from this same downfall like Fedora. It is a little different but I believe it to be slightly more intuitive.