2000 Dodge Caravan No start

Bear with me, because there are a lot of variables to this problem, though I imagine the solution is rather simple.

The problem started two weeks ago. The key lock cylinder got stuck and my wife could not turn it to start the car. She left it in a parking lot and got a ride home. I went out later that day, and after looking up the problem on the web, I tried giving the key three taps with a small wrench. That worked like a charm, and I was able to turn the key. But when I turned it to the START position, nothing happened. Thinking that perhaps the battery had been drained, I hooked up the jumper cables. But still nothing happened when I turned the key. I disconnected the jumper cables and sat there bewildered. Then I tried turning the key over and over. Lo and behold, on about the tenth try it started right up. The first day.

For the next three days, things were fine. The lock cylinder would stick about half the time, but a little jiggling of the key, or a few light taps, and the car would start right up. But on the fourth day, the 'no start' problem returned. I turned the key and nothing happened. In light of what had happened before, I simply repeated the process of turning the key repeatedly, and eventually the car started. We had a lot of chores to do that day, so we drove all over town, often having to turn the key five to ten times to get the car started (and often having to tap it with the wrench just to get it to turn).

After leaving the last store, we got into the car, and this time no amount of turning the key would get it to work. When the tow truck showed up 2 hours later, the guy said the problem was in the ignition somewhere, and he showed me how to start the car with a paper clip by connecting two contacts in the fuse box.

The next morning, convinced that the key lock cylinder was the problem, I took it to a locksmith. They looked at it and said it was fine. "It might be sticking a little, but if it's turning, it's doing everything it's supposed to." Well, it just so happened that one of the locksmiths had been a car stereo and alarm installer for 15 years. Just as I was about to leave, he noticed a little red light under the steering column. "Is that an aftermarket alarm?" I didn't know anything about the alarm, as I bought the car used a year ago. He disconnected the alarm and turned the key, and the car started right up!

He told me it would be best to completely uninstall the alarm system - which he did, and charged my $50 for it. When I got in the car 30 min. Later, I became aware of a new problem. I turned the key and nothing happened! What the #$? I had just seen it start right up on the first turn half an hour ago, and now nothing. The locksmith told me that I had to push the key into the column as I turned. I tried it, and it started.

So now we could start the car with the key, but there was this new problem of having to put a lot of force pressing the key into the column while turning it. If you didn't apply enough force, it would turn to the START position and nothing would happen.

Well, that worked for about a week. And then it stopped starting again. No amount of force inwards would get it to start.

So that's where it stands. Right now, the key lock cylinder still sticks sometimes, but you can always get it to turn eventually with some taps. When you turn it to the START position you can hear a single click coming from around the fuse box if you are under the hood. But other than that, nothing. But we can still start right up with the paper clip trick. Thank goodness that tow guy showed me that, or else we would have been stuck without a vehicle for the past week. On the other hand, my wife refuses to drive a car that has to be started that way, and I can't blame her. So something has to be done. Any ideas?