I have run into this problem on a few first gens, the lock seems to get stuck in between lock and unlock. I have had sucessfully got the latch back to normal working condition by spraying some WD40 down onto the latch from the top of the door with the windows glass rolled all the way down. You should have a straight shot.
Then you have to work the door lock up and down a bunch of times and also work the door handle.
If you want to remove the door panel to do this you will need the tool to remove the clip from behind the window crank and door handle and also take out all the screws.