I have a 1990 Escort GT with 161k miles on it that has had a high idle and battery drain. Basically on these cars if you are not a mechanic and you don't take it to one you will probably be chasing them down for a while, so long as the car is driving.
You should probably figure out the stalling issue first before you can proceed to the high idle situation, unless they are related.
Pull the codes which there are probably some based on what you described. Otherwise check the pcv valve and plumbing, canp valve, egr system, vane meter and air hose, all vacuum lines, basically anywhere unmetered air can get into the system. I had the steel backpressure line from the exhaust header to vacuum regulator break off, but if you don't have an exhaust leak you are OK.
Rule out the simple stuff, one-by-one I plugged my pvc intake on the throttle body, accessory manifold vacuum (except the fuel pressure regulator, you can test that with a vacuum pump), and egr tap into the throttle body. If the idle decreases there is probably an air leak in that part of the engine. If no difference, an air leak is probably somewhere between the vane meter and the cylinder head. Could be gaskets, injector o-rings, IAC valve or something else.
The battery drain is from an electrical short somewhere, or a bad switch. Check the draw with an ammeter from the neg battery post to neg battery terminal with the car off, it should be less than 100 milliamps, maybe less than 50 not sure. If greater, begin pulling fuses and look for a drop. This will at least isolate the circuit for you. The radio and clock always draw from the battery, but this is supposed to be like 25 ma or so, not sure.
Pull the codes and post them, I can probably interpret them for you based on my experience with my car.
Matt