Wipers and light draining battery when car off and/or battery's dead?

[tomanychoises32]

98 6 cyl mercury mystique or ford contour. Basically the same car. Mine's a mystique.
4 months ago: the battery died overnight every once in a while. The wipers went on while driving sometimes but the switch was off.
Then the problem turned into: i would close the door after turning the car off, but a light on the door stayed on or sometimes turned on after I walked away from the car and would drain the battery overnight. I had to kick the door to turn the light off. I only had to jump it maybe twice in this stage though.
Then, the problem's this: None of my interior light work. The dashboard light works. I jumped the battery, it starts in two seconds. The wipers always go on right after starting but then turn off. I drive around to charge it up but it loses power overnight. If i start it a few hours after jumping, it would almost not start but did.
now: it won't start or even click right after turning it off after driving around after jumping it. Hopefully it's just the original battery, but the wiper and interior light issues point elsewhere. The battery + side was full of green powder stuff. It's a 40r battery, what can i use in place of that since I can't find a 40r used cheap if it's the battery?
I'll cut wires to interior lights, glovebox, etc if I don't really need them if it makes an easier fix.
Should I bring it to autozone for free testing and charging? http://www.autozone.com/autozone/ino...s/services.jsp

thank you so much.

[gmtech1]

Yes, get the battery and charging system tested. Low voltage will cause all kinds of issues. It sounds to me like the battery toast though. You may also have problem with the drivers side door switch. I would not recommend cutting any wires,it may cause a short. Why not just pull the fuse for the lights?

[tomanychoises32]

ok i won't cut any wires. I threw the idea out there 'cause i imagine finding a short to be a nightmare with wire testers and ripping the dash out and stuff and not really knowing what i'm doing. FWIW, i cleaned the corrosion and coated all in vaseline.

[tomanychoises32]

two shops tested the battery to be dead. I got a new battery. It's been in for a few days and no problems, so hopefully there's no wiring issue that drains the battery.
thanks