My trans won't shift / town country

Wow, that's a lot of information to digest. If it's stuck in second gear, that's "limp" mode that allows you to drive it slowly to a repair shop without needing a tow truck. You can get an idea of the cause by observing when it goes to limp mode; as soon as you shift into a forward gear or after it makes an up-shift.

If it won't move at all, check the fluid level but suspect internal damage.