I started out using the current-stable nvidia driver from ubuntu's additional drivers installer. After installation the desktop (nautilus?) just doesn't seem to load. I have a mouse and the background from the login screen. The only way out is ctrl-alt-backspace and login with 'ubuntu 2D' or safe mode.

I'm running dual monitors on an Nvidia 8800GS with 64bit Ubuntu 11.10.

I'm not entirely sure how to go about diagnosing this issue. Does anyone know how to check which driver is in use?