Girlfriend's laptop just died, need HELP troubleshooting.

[shipitkthx]

My girlfriend has a Toshiba Satellite A105-S4384 Laptop. She uses it mostly for gaming. Today while she was playing it completely froze up with a blank screen, this has happened before and she just unplugs the power cord, removes the battery and pops it back in. Today when she tried to start it back up it comes to the windows error screen where it asks if we want safe mode, last good known config, or normally. Now typically I am a pretty good windows troubleshooter and have been able to fix 98% of my problems on my own but I have never not been able to get to safe mode. All options result in a few things starting, then the PC completely restarting and coming back to the same screen.

Ive tried googling this and came up with several things.

A. Some sort of error with the boot settings. The problem here is that the OS is OEM and all I have is the toshiba disks which are useless unless I want to do a full reformat which I'm not sure is necessary yet.

B. Overheating? I also read the chronic restarts could be caused by overheating in which case the PC would shutdown as a safety feature? We are both smokers which I also realize could be a problem. I tried hitting the main duct with a duster but it didn't fix the problem. I have a tool kit and I am comfortable enough looking under the hood but I'm really not sure what I need to be looking for.

Any suggestions?