key will not turn in my 2000 T&C.

Best guess is the lock mechanism is just worn out and there is a broken spring on a pin inside. This is a big headache if you can not get the ignition lock cylinder you already have fixed, otherwise it means a new ignition switch, programming and re keying the doors. They should be operable in case the remote fob system fails. (If it has one) But: before you do anything much, try wiggling the steering wheel as you turn the key, and if you have 15 keys, a flashlight and a charm on your key ring, swinging all the time, that may have been the cause, all that weight

Tap the key with a hammer til the tumblers fall into place