Have you checked your q3config file? I remember when I set some video settings that were supposed to be the native resolution of my monitor, it got an "out of range" error and would crash on me as well whenever I would start it in full screen mode. I had to essentially go into the config file and use a "safe" resolution after getting tired of uninstalling and re-installing UrT a couple of times. I haven't been in there in a while, but I think there is a var in there to use a specific OpenGL version. If there is you might try changing it to an older version and see if that works. If the current OpenGL version in the nVidia driver is messing up, maybe forcing the card to use an older version would make it work in full screen mode again? Also you might want to check that the resolution in the config file is not set higher than the native resolution on your monitor.