2001 Buick Regal It won't start some times, not at all now

In the last year, maybe 7 or 8 times the car wouldn't start after you drove it a little and shut it off. The battery is fine, it doesn't even try to turn over, click or any thing, the gauges all go dead while you try it. Usually after setting for 3 or 5 minutes, I also move the shifter back and forth, and keep trying it, it will start. Tonight it wouldn't start after setting all day. It seems the key is not shutting off all the way, but I can pull the key out, and can pull it out with it on also. I jumped the solenoid, and the starter cranks. How does the shifter position tie in to the ignition switch? Any ideas? Thanks, I will donate if you do help me. Thanks, Tony