Graphic card doesn't work

Hello, I've been having some problems with my graphic card.

I've got a laptop XPS M1710, Vista and a Nvidia Geforce Go 7900 GTX

Yesterday, I installed an old game ( from 2001) and after that I watched a video on viddler.com in full screen.
I had some graphical glitches with any moving image on my laptop ( including scrolling ). I restarted my laptop, and tried to watch the video again. After which the laptop crashed and successfully restarted, I tried to watch it again and now it wouldn't restart.

It would give me the Dell loading screen with graphical glitches on it ( red lines and such ) after that the load thingie and after that instead of the windows logo, a blue screen with some info on it.
So I went into safe mode, and my screen was littered with these small blue squares/blocs. Figuring it had something to do with my graphic card, I disabled that through Device manager, and managed to restart in normal mode. If I enable the card, I can't start up except in Safe Mode.

So the problem is most likely my graphic card. Reason I said I installed an old game is that after that I had problems with the video, ain't sure it is connected. Could it be that the game messed up my graphic card? Is it possible my card is irrevocably damaged from a few crashes?

I already did a virus scan and updated to the newest drivers. Please help me with this, cause I really don't want to buy a new card and I'd be really surprised that a few crashes could break it so easily.

Thanks for the reply.

I am absolutely positive it isn't because of the heating. I've place my laptop higher and put a ventilator next to it to ensure the cooling is good.
Also I've used this card for a year now, so it has enough juice.

With a drive cleaner, do you mean something like CCleaner? If so, what do I have to clean specificly, if not, whats a good drive cleaner?

It isn't a chipset I think, and my warranty has already expired.