Graphics Problem

I'm back, yet again. I recently updated the graphics driver for my Nvidia 260M card on my laptop. After a few reboots, the system would give me a message before fully loading asking me to choose from several options for my graphics card. i would always choose "restart x-server" or something like that. after a while i did not get this message anymore. Today i noticed something wrong with my my mouse pointer. when i press control to locate my mouse, the graphics came out all wrong. so i went to system>administration>Nvidia x-server settings and itt gave me the following message - YOU DO NOT APPEAR TO BE USING THE NVIDIA X DRIVER. PLEASE EDIT YOUR X CONFIGURATION FILE (JUST RUN `NVIDIA-XCONFIG` AS ROOT), AND RESTART THE X SERVER.

When i run the xconfig command i get the following

shagmaster@ubuntu:~$ nvidia-xconfig

WARNING: Unable to locate/open X configuration file.

ERROR: Unable to write to directory '/etc/X11'.

shagmaster@ubuntu:~$

What do i do? still reading Oreilly - Ubuntu Up and Running (2010) and have not got to the point where they teach how to fix problems like this. thanks