Start off by removing all the NVIDIA* packages. Do an
rpm -e NVIDIA_GLX NVIDIA_kernel (preferably not with X running). If you installed the wrong kernel driver, then GLX won't load either.
Basically, revert to fbdev (or figure out how to surf nVidia's site with lynx or links).
Then, go back to the download page, and get the NVchooser thingy that's there. Save it somewhere (like your home directory), then open a terminal and
sh NVchooser.sh from that directory to run it.
It'll print out which packages to download.
Once you've gotten those (or just figured out which ones they are), quit out of X and install them as described in the README -- kernel first, then GLX.
Then, make the changes to your XF86Config-4 file, as described in the README.
Then, try a
startx to see if it all worked. If something doesn't, then copy /var/log/XFree86.0.log to somewhere else (like, again, your home directory), undo the changes to XF86Config-4 (or copy the backup file that you did, of course, make
, over it), and startx again with the old driver. Then attach that XFree86.0.log file to a post.