I'm have much computer experience but am new to Ubuntu.

Standard installation with nothing out of the ordinary changed. Basically default settings all the way.

I typed in sudo apt-get install ubuntu-desktop and it tells me it's already installed. Good. So it should work. I type sudo/etc/init.d/gdm start and the screen goes blank for 8 seconds three times in a row and then back to the command line. I have also tried gdm start without the path before and it says GDM already running. Aborting!

I have 8.10 and it's a valid disk (no errors).

Can someone help please?