It was a broken regulator (cable in the regulator, specifically) and a local shop charged me $235 for parts and labor. Works like new now.
The interesting thing he told me was that these tend to fail, not from use, but from NOT using them often enough. The window develops a "set" in it's channel, and it just puts too much strain on the regulator when it tries to "break" the window loose.
Thanks again for everyone's help. The lesson learned here is to USE all the stuff in our cars once in a while, the car needs the exercise.