What could be the cause of why mar car is not starting and to get it started again?

Hello, I have a 2001 Pt Cruiser (Touring Edition) and I would like to explain that about two months ago the Engine and Oil lights started coming on by themself at night, I turned the ignition on during this and could not get the car to turn off. This happened a couple times. The first time I walked about 5 blocks while it ran, to get help to turn it off, and a guy came back 20 minutes later and we just undid the battery and it stopped. Second time, I was at 711 and the car would shut off, didnt know how to shut it off because the ignition key wouldnt turn it off, and it wouldnt come out of park. Anyway, it overheated so badly the coolant burst out of the bottle, and no one could figure it out, a man came about 20 minutes later or so again, and I believe pulled out the Spark Plug, and it shut off. It did it a third time and I went to the fuses and pulled out the Auto Shut Down Fuse" and it shut it off immediately. It stopped doing it after that for about a couple weeks, and then I had gone to the store one evening and came back to the car, where the lights and battery still worked, but couldnt get the car started. I got a security man with his truck to come and jump start it to turn it over, and it took about 15 minutes, and started. Recently over a few weeks ago my car began overheating, a friend suggested it was the thermostat (as well the temperature gage for sometime has taken alot more time too move heat temp. Upward) so, I was able to get someone to take out and put in a new thermostat. But was told in the process there was a leak coming from the water pump. He said I could get some stop leak to temporarily stop the leaking and add water. So I got some silvery matallic stop leak at Oreillys Auto shop, and poured it in. However, I poured the whole bottle in the radiator as the bottle instructed and drove it 20 minutes. As I reached over the Aurora Bridge, I heard a rattling and got off and the car really overheated and froze in the street. I pulled it over and let cool down, then added more water. I have driven it since, for about a month, just adding the water, slightly over heating at times. But ultimately ok. Within the last couple nights the car engine and oil lights came on again while I was driving unexpectedly, the car did not overheat, but it froze up and I pulled over and was unable to get it started again. I tried to reset it and also tried to get it jumped 2 times and no success. It starts like it wants to turn on but wont. Can you tell me what may be causing the car lights to have come on? And why it wont now at least start up? I have been told, read, and am guessing it might be the Starter/ Silinoid, Ignition, or the Timing Belt? Right now my car is sitting and I really need this car to start again at least and then fix the water pump.