ok i just attempted to install the lastest Nvidia drivers onto my RH machine, and i believed i installed the wrong rpm, because now when i try to start X it doesnt work and if i manually type in X at the command prompt it will say "fatal server error, no screens found" ive tried to install the right rpm and it doesnt work, is there a way for me to uninstall the old rpm, install the new one and get the x windows thing to work? also if worse comes to worse and i reinstall linux would my user name and user settings be overwritten?

You could edit your /etc/X11/XF86Config-4 file instead. Instead of typing X or stsrtx, type mc, as root. Then Midnight Commander opens, a great little file manager. Navigate to /etc/X .. and press F4 to edit the file.

You will see a section like this one -
Section "Device"
Identifier "device1"
VendorName "nVidia Corporation"
BoardName "NVIDIA GeForce2 DDR (generic)"
Driver "nvidia"
Option "DPMS"
Option "CursorShadow"
Option "NoLogo"
EndSection

Change the driver to "nv", save, exit and then try startx. It should work.