Vista - Can't Boot Laptop After Vista SP1 Installation

I formatted my HD about a month ago, and only got around to installing Service Pack 1 on Vista yesterday. Everything was working fine... and then after a restart my computer no longer boots. It gets to the vista loading screen just fine, but then it disappears and proceeds to a blank black screen. I notice that at all times the HD light on my computer constantly flickers on and off. At first I thought that the update is still going on, so I left it like that overnight. It didn't change by morning time.

Booting in safe mode stops the loading on crcdisk.sys. I've tried booting using the Vista CD. I tried startup repair and command prompt for fixboot and fixmbr, which only makes starting into safe mode automatically restart. I've tried System Restore to the point before SP1 was installed, but the restore process also hangs on "finalizing files", and doesn't get anywhere.

Am I stuck? Is there anything I can do? I at least want to back up the files on my computer before any format is tried.

I'm so tired of Windows =( I've lost all resolve.

Your advice will be highly appreciated.

Anyone care to help?

Can you try safe mode wth command prompt, then typing sfc /scannow, then run a check disk scan.