1989 Chevy Corsica

1989 Chevy Corsica

I have two problems. The first one is: when driving around and coming to a stop my car will stall, this happens after a while of driving (30 - 45 mins or so) or after I have had to apply the gas to get going quickly instead of gradually. I'm still trying to determine what causes it between the two. The second problem is: I can not turn the ignition! It's as if the ignition is locked in place, I can't turn the key forward to start the car or backwards to turn on the radio. I have tried forcing it with no luck. I also noticed (after my ignition locked up) that my temp gauge is at the top red mark and my engine itself feels rather hot, even after an hour of sitting while in cool weather.