BMW: ignition problem, e36 325i, time melissa

Question
I own an 1992 e36 325i. I went to start my car put the key in the ignition and it went in but when I turned it it only turned to the on position and no further then that so I can't start my car.  I can listen to the radio but can't go anywhere.I tried wiggling the steering wheel. I tried turning it past that point but it just won't go.  Some people said its possible metal dust/shaving get in there over time from use and jam it up. Others said your key barrel is shot and some said your locking mechanism is jammed. Your opinion would be appreciated.  But my question is since I can't start my car with a key, could I over ride the whole key not turning problem by installing a push button starter?  I have free access to one and not a lot of money to drop into a ignition right now. I have some mechanical skills I just don't know a damn thing about ignitions. Any information will be greatly appreciated. Thank you for your time.

                                Melissa Rose
                           bmwanimalhelper@yahoo.com

Answer
Melissa,
 Its always a pleasant suprise to see a lady who is willing to work on her own car.  Congratulations, and I hope this is a continuing trend.
 Anyhow, the people who have been telling you what the problem could be, are probably right.  As I cannot see the ignition switch, and cannot physically offer any help, I am left with what you told me.  Before trying any wiring or anything like that, take something and tap on the ignition cylinder.  What I mean is, remove the key, and take a wrench or screw-driver and tap on the cylinder as to maybe knock loose what ever is holding the key from turning.  MAKE SURE NOT TO DAMAGE THE CYLINDER, ESPECIALLY WHERE THE KEY IS INSERTED!  I would find something like the handle of a screwdriver that is hard, but wont dent the metal.  You just want to vibrate the cylinder enough to possibly dislodge what ever is holding the cylinder.  
 Since you can turn the key to the accessory position (radio works, but nothing else) it is definately a malfunction in the cylinder.  Wiggling the steering wheel will do nothing, except vibrate the cylinder and possible dislodge what ever is stopping the cylinder.  You could possibly use compressed air (like the cans sold in computer stores) to blow in the key hole and maybe that will help as well.
 As far as rewiring your ignition to start via a push-button, I would really save that as a last ditch effort.  In that I mean, I would rather you replace the whole cylinder than to have to do that.  So in the case that there are no cylinders left, anywhere... you would probably have to resort to wiring the car up to start via push button.  The problem right now, is that even if you could get the starter to spin and turn the engine over, the car still would not start.  The key would have to be in the "on" position, which is one spot further than your key will currently turn to.  So you are really out of luck in that department.  
 Like I said earlier, If you can't tap (gently w/o breaking anything) on the cylinder and get it to turn, I would call a locksmith to have a look at it.  He will be able to replace the whole thing, for far less headache than if you rewired the ignition.  Not to mention, anyone could potentially bust out your window and press a button to get your car started.  
 Good luck, and dont hesitate to ask any more questions!
 Josh