Today I noticed that the passenger window behind the driver's seat was open about an inch. When I tried to use the control to bring it back up, I heard a kind of grinding noise, but the window didn't move. I tried several times, with the same result. I was able to manually push the window back up, but it can easily be pushed back down. Does this sound like something that might be easily (and cheaply) fixed by my regular mechanic? Or do I need to take it to the dealer? It's still under warranty, but if it's cheap enough, I'd rather take it to my regular guy as it's much more convenient. Any help would be appreciated.

This is not a cheap fix. Get it taken care of under warranty. You need the documentation anyway.

[Edit]. Your regular guy may be good, but us dealer guys know your vehicle better than 10 of those guys. Factory training, special service tools to repair the concern, just to mention a few. It's worth the drive. Put a Beach Boys tape in and enjoy the ride. :D