All the fuses checked out. The battery registered 2.5V. We took it to the auto parts store. Their battery tester said it was fubar. We bought a new one, put it in, and everything worked perfectly. Problem solved. Yee haw.

P.S. While the car had been sitting, the emergency brake managed to seize up. Luckily, toggling it on and off about ten times fixed it. I love cars, really I do.