you might be able to do the old Ctrl+Alt+Delete
or if everything is loading and then not showing anything you could try Alt+F4 and then press Enter
Edit: Restart might be possible with Alt+F4 and then up key or down key then Enter to select one of the other options in the Shutdown menu
lol another one is Windows Key then Up Key then Enter <--this will probably just shut down in Win7
try these while in windows when you can view what is happening.