Vista Ultimate - No desktop

I have a tower here with Vista Ultimate. It loads to the login screen just fine. I type in the password, it's accepted, the login screen closes as usual and I get the spinning circle thingy, then I get the mouse cursor, and that's it. Black background, CTRL_ALT_DEL does nothing, clicking does nothing, keyboard does nothing, the mouse moves the cursor as usual and that's it. I booted to the Vista install disc and tried Startup Repair, no dice. I also tried the System Restore and successfully rolled back to Nov 28, but that didn't fix the problem. So.... any ideas? Suggestions? Advice? Comments?

Thanks!
:-D

(oh yeah - I'm going to run a CHKDSK now.... *fingers crossed*)

 

something wrong with explorer i would say