Based on reading forum posts and my own difficulty with Intel video chipsets, as well as using some scripts to standardize an install, the following should get a lot of people going, I hope.

1. Get into failsafe mode: hit ESC at boot and choose a failsafe kernel; go to the root prompt when able.
2, Get rid of Compiz, completely: sudo apt-get -y remove compiz*
3. 8.10 seems to default to a blank xorg.conf: run Xorg -configure and move the file it creates to /etc/X11/xorg.conf
4. Make sure you have a .gnome2 directory in your home folder: rm -fr /home/(username)/.gnome2 ; mkdir /home/(username)/.gnome2 ; chown (username)username) /home/(username).gnome2

5. Reboot normally, then make sure you've chosen a GNOME session in the bottom-left corner menu (set as default if asked).