My emergency brake seems to be stuck in the on position. I pull the release lever and the pedal comes back up, but the brake is still on. Something wrong with the whole assembly or maybe it's just an old cable or something?

Year?
Brake cable could be siezed.
Parking brake mechanism can be siezed.
Are the wheels locked up? Or is the light just on?

1982.
The light isn't on and the wheels don't lock, but I can tell it's on. There's a lot of slack in the pedal and you can just feel that the brake is applied.

Check the cables to make sure they can move freely. Check to make sure the brakes are properly adjusted. Make sure all the springs in the system have the proper tension.