I just got my computer back today. The shop said it was working great now. The issue was that I would get fuzzy blocks on my pc screen when playing DF and it would completely freeze my screen. Well needless today that they reinstalled windows for me.
But it still does it. Its fine when I'm web browsing, watching vids, listening to cds etc. But as soon as I go to play df it gives me black fuzzy blocks. Could it be my vid card? It's an 8800gt, and I've had it for about a year and a half? HELP please!

Let me get this right: after a reinstall of your OS you still have that problem? Have you tried to uninstall/reinstall the graphics drivers? If you paid for them to help you I would take it back to them and tell them that you still have a problem. If it still has the same problem after a OS reinstall and the graphics drivers are correct then it could be your card. If possible can you try another card in its place,; one that you know works. If it is a different model you will have to uninstall the drivers and install the ones for the other card. If it is a new card & still under warranty I would contact the manufacturer.