Win7 not booting normally (Safe Mode ok)

[Fuzz]

First post here. Suddenly started having strange problems.

Running Win7 Professional SP1 64-bit on an Alienware MX17 laptop. 8GB RAM, 1TB HDD. Have had it for over a year, everything's been working fine.

Just yesterday, it started acting up after updating my (ATI) video driver -- the screen would freeze completely at random times (usually after waking up from Sleep or screensaver). Would go back to normal after rebooting.

Well tonight I have a new problem. Cannot boot normally anymore -- shows the "Starting Windows" screen fine, then screen goes blank (as if in preparation for the blue login screen), but screen stays blank, cursor frozen, and all HDD activity stops. No change even after 10 minutes (longest I've waited).

I can boot up in Safe Mode, and running CHKDSK (via command prompt) shows no problems.

Thinking the video driver might be the culprit, tried to do a System Restore, but cannot. Says: "The file or directory is corrupted and unreadable". Then System Restore exits itself saying "Catastrophic failure".

I have no idea what went wrong and how to fix it. Any ideas on to fix?
Thanks.

 

[Fuzz]

Now my machine is not booting in Safe Mode either. Last time I booted in Safe Mode, I set it to do a disk check on next restart (it couldn't test C: because it was in use). On the next Safe Mode reboot it loads all the drivers like before, but then after the last driver it stays there (on the screen of loaded drivers), and the HDD light stays on steady for up to 2 hours with no change (maximum I've tried). No matter how many times I try Safe Mode boot, same thing.

Trying an Alien Respawn right now -- thankfully all my data is backed up (mixture of Carbonite and external drive). Let's see if that works.

Any insight/guesses as to what happened and why? Don't want to go through this again. In about 20 years of owning PCs, I've had something similar happen only once (motherboard got fried). Before this incident, this machine worked flawlessly...now I don't want a repeat of this, so knowing what happened and how to avoid it will be useful.