I've successfully installed the NVidia drivers for my video card and it works wonderfully, Unreal Tournament 2004 plays flawlessly, but I have one problem. I prefer to run my screen's refresh rate at 60 Hz, it's much sharper and I like it, but after installing the NVidia drivers the only refresh rate available to me is 85 Hz, no higher no lower, and occasionally after running at this refresh rate for a few minutes my monitor tends to make a high pitched squealing noise, telling me it can barely handle 85 Hz, so tell me, how would I go about editing my Xorg.conf file to allow me to use refresh rates lower than 85 Hz?

Become root.
Make a backup of /etc/X11/xorg.conf
Use your favourite editor to edit /etc/X11/xorg.conf
Find the part that says Section "Monitor"
Make sure the values for HorizSync and VertRefresh correspond to what your monitor will support (Look in the manual / search manufacturer's website).
Save the file.
<CTRL><ALT><Backspace> to restart the X server.

HTH