Battery was dead. Put a charger on and have strong horn, lights, and everything else. Cannot get car started. Cannot remove key from ignition. Is there some sort of security system on this car that is activated when battery runs down completely? Seems like I have enough juice to start the car. Anybody have an idea what is wrong and what I have to do to get car started?

 

Sounds like its an automatic. Check to see if the car is in neutral/park. These are the only positions where the car can be started or the key removed

 

Park is the only position where the key can be removed. Is the button on the gear shifter broken? If the button is broken it will be difficult to put the car in park. Try wiggling floor shifter while the car is in park so that the button on the shifter will release. Now try turning the key to the off position. As to why the car will not start; does it crank? Was it running fine before the battery died? Maybe a new battery is in order. Is the battery over five years old?