I installed Ubuntu by loading the live cd and using the install icon and following all the directions. This is being dual booted with WinXP but that doesn't seem to be the problem. Anyway, whenever I load Ubuntu, it does all the setup procedures (the scrolling text) and goes to boot into X but instead all I'm greeted by is a blank screen. I tried pressing Crtl + Alt + F1 (if that's the right key combination) to get the prompt but nothing happens....

However, on other times I've booted Ubuntu, it works just fine. It seems to be a purely random event.

Should I try running the sudo dpkg-reconfigure xserver-xorg command when it does load into X & gnome, sudo dpkg-reconfigure xserver-config, or something else?

Yeah, boot in to rescue mode (from grub menu) and run "dpkg-reconfigure xserver-xorg"
if that dosen't work try "dpkg-reconfigure -a"
you could also try, "apt-get --reinstall install xserver-xorg"

I did sudo dpkg-reconfigure xserver-xorg and used the vesa driver instead of the ati driver and now it works fine. Sure I won't get 3D acceleration, but I wasn't expecting that on a Radeon 7000 (which seems to have problems with X). Thanks!