bricriu suggested asking for a printout of the test results (so I could google and see what's up), but red flags went way up when I was told they couldn't do that. I took my machine and ran! (For what it's worth, he said the motherboard was fine, but stuck to his story of the graphics card being on its last legs.)
Once home, I set it up on top of my desk instead of under, but this doesn't work out. While the fans aren't loud anymore (though there still is a difference between running WoW and not), the fact that it's six inches from my ear means it seems even louder than before. I want to keep it off the floor though, it will get less dusty and will be way easier to clean.
For some odd reason, all my settings were gone when I finally booted back up. (Probably like losing all my radio stations in my car when I needed a new battery.) My display was dark as heck, looked horrible -- I'm still fiddling with things to try to get them set back correctly.
Debating on what sort of review (if any) to leave on Yelp. The guy was very nice, though they did take longer than they said it would. The issue is mostly fixed, but there's the whole up-sell thing.
Alas, I still have a credit of $30 or so with them, which he said would cover the install of the new graphics card, if/when I want that done. IF I need a new one, I'll likely just buy one and maybe let them do it, assuming they can do it the same day. (Yeah, I know it's easy to do, but it really makes me nervous to do things inside my computer myself.) No option for a cash refund, since it was through Groupon.
So: Woot! *hugs computer* Never leave me again!