Black Screen - Not a Monitor Problem

[greenskittle]

Hey
Yesterday I (stupidly!) turned of my windows vista computer while it was busy running windows updates.
Since then it wont load up the desktop of my computer - I know its there because I can hear the narrator saying whats on it.
The computer shows all the loading screens before it.
I know its not the monitor because the computer loads up fine in safe mode
It shouldnt be the screen res. cause it had been running that screen res for a while before hand

What could it be? and How do I fix it?
Please Help

It was recommended that I do System Restore - this failed.
Also running a System Repair failed as it found nothing wrong.
I cannot run a windows update.

I was also told:
"some of the drivers or system files were affected when you shut it off. If you cant boot in normal mode or do system restore or anything press f10 or f11 or f9 anyways do a reset computer to factory settings basically when you first bough it or just reformat
you might also know it as PC restore/recovery (NOT SYSTEM RESTORE)"

I dont know whether this would work - But it requires my vista disk... and I'm really unsure where that is...

Please Please Please Help!