Our 2005 Chevy Trailblazer LS is locking the key.

Our 2005 Chevy Trailblazer LS is locking the key in the 'on' position and we can not get it back to the 'off' position unless we tilt the steering wheel up and down.(Or better yet slam the steering wheel up or down). It sometimes starts fine without a problem but is starting to get to be more and more of not starting and then locking up. When we try to start it and it doesn't start it makes a clicking sound like it would be the starter, but then why would the key get stuck. We have tried putting it in neutral to start it and sometimes that works but not all the time. There is an after factory AstroStart remote starter on it and that is no longer working either. Each time the car starts the clock also resets but it does not reset the radio settings at all. The heater and a/c is also an issue but we don't think that has anything to do with key/ignition. The heat/ a/c will push out some when we are driving on the highway, but doesn't at all in town. (That's the smaller problem) Any help would be greatly appreciated! We can live without heat/ a/c, but need car to start to get to work, home, etc.