[HELP] 1990 New Yorker won't start!!!!!

[Kaiser Soze]

I have a 1990 Chysler New Yorker with 143,000 miles. Never been in a accident, body, paint, and interior are all perfect. But I have always had some electrical problem or another. So here's the thing. Last week my girlfriend used it to go to the store. She called me to come over as the car wouldn't restart. Voltage was low so we had to jump it. It died as soon as I tried to put it into gear. I had to rev it up while appling the brakes to make it home. The moment I put into park she died. I bought a battery charger and all seemed to be find, except the car would not hold the charge. So I bought a new battery and everything seemed fine. Now she won't turnover. Voltage is up and the car is not draining the battery. You can turn the radio and all the accessories on with no problem. The moment to try to ingage the engine, everything goes dead. I have to disconnect the battery to "reset the car" and get it to have power again.

My friend (who works for BMW) came over and after messing around with it for awhile got it to start. In the hood on the left is a box with several fuses that are not burned out. The box looks brand new with no corrosion. After I reset the car, when I connect the ground I can hear a faint click in the box, athough I don't see any moving parts. We smacked it a few times and it seemed to work for a few days. I drove to work and then as I tried to get home it did the same thing. After unplugging the ground and reconnecting it the car started. Once I got home though, it hasn't started again. The starter is fairly new as I had replaced it a few years back. Any ideas on what I should do to try to fix it? I can't even get it to a mechanic as it won't start, and paying for a tow will be pricy.

Other issues with the car, that may or my not be part of the problem:

Odometer stopped working.
Airbag light is on
AC does not blow cold
Sometimes gauges act funny. Temp spikes then drops
Sometimes the speedometer doesn't work. I'll be driving and it stays at 0 then all of a sudden it fixes it self.