In the Control Panel under Graphic Card Options, I set it to use EXA instead of XAA, and I now have no desktop at all... just a blank screen. Does anyone know how I can somehow set it back to XAA. Thanks very much.
After much thought, I booted the Live CD, went into the laptop root files and edited the xorg.conf file. There is a line in there (Option AccelMethod "EXA"), in which I changed the "EXA" to "XAA", rebooted, and got the desktop back.