please download the driver and read the README file, you'll have to do it someday, believe me...
btw: when installing nvidia driver, please shut down X the right way:
log in as root
/etc/init.d/dm stop (kills X)
then install nvidia driver and modify /etc/X11/XF86Config-4 (with vi (press INS for editing; press ESC :wq ENTER to save and exit) for example)
then bring X up again:
Alien is my name and headbiting is my game.