What can I do about a touch screen that won't work?

Thank you! The touch screen of our 2009 Chrysler Town and Country has
been unresponsive at times in certain locations of the screen, particularly the
top left area, and now seems to be completely unresponsive in that area. On
the screen for radio, SAT, TV, my son pushed where it said TV, and it is stuck
there. I can no longer get on the radio because it is totally unresponsive to
touch now. The strange thing is, when I hit the menu button and it takes me
to the SAT Video Menu, I can touch functions in that left upper corner, and it
works just fine, but is again unresponsive in that area when you switch from
the Radio to Media screen. I was wondering if a new screen is needed or
something else? Also, is there a way to simply get it back on the radio by
going to factory default settings in some way?