i had this same problem when i first got my truck, and it turned out to be a penny that was lodged inbetween the shifter and the end of the shifting range under the trim panel. pop the trim piece off around the shifter and see if anything is in there that will prevent it from going fully into park

 

I turned the switch to "on" when I first did the "stuck key" search on here. I shifted from P to D then back up to P. I don't see anything keeping it from going into Park...

It's not on a hill, it's in my garage.

 

But did you put it in neutral and try to start it?

 

Yes, it does nothing.

 

It's starting to really sound like a bad ignition switch. Anything electronic can fail at any time without warning or reason. The no start problem could be related to the alarm system but the key not coming out wouldn't be caused by the alarm.

 

The alarm did go off earlier today when I opened the back door. However, that was before I got back in it to come home and it cranked fine then.

Now when I turn the key it doesn't even click like it's not going far enough. Kinda seems like the switch to me, but I am NOT a mechanic by any stretch of the imagination.

 

What caused the alarm to go off? Just opening the door? Were the other doors locked? The alarm going off earlier makes me think it is related to the alarm but that still doesn't explain the key not coming out. If you don't mind I'm going to pick your brain until we figure this out or we both run out of ideas.

 

I still think it is a in the wrong gear thing, but maybe not.
When you put the truck in reverse do the back up lights come on?
I have a similar problem to yours with my FedEx van, the gear pointer does not line up with what gear I am in.Reverse is park, neutral is reverse, drive is neutral...you get the idea.
If it is not put in park hard enough then I cannot remove the key. Even though the pointer is pointing to reverse it is in park.
If that is not it then it sounds like you may need a new ignition switch.

 

Yes all the other doors were locked. Sometimes the back door doesn't lock when I use the remote. So the alarm is set and when I open the door it goes off.

 

The door lock actuator in the back door is bad, thats why it wont lock when you use the remote.
Get some grafite and spray inside the ingition switch and see if that does the trick.
Just use a small amount though.