Deliberately crashing the car is iffy at best. It could incapacitate the perp or you or even cause him to trigger off a round. I agree with a couple of posts who have said "don't go with the perp anywhere". Chances are you won't come back. I'd bail at the first opportunity.
At least, that's what I would do if I were dumb enough to get into this situation in the first place. As you point out, it's a flawed scenario, but it DOES happen every day. And keep in mind TV isn't anywhere even CLOSE to reality.
When I'm waiting in a parking lot: I am armed, the doors are locked, my seatbelt or open, my head is on a swivel, and the engine is running. I'll also pull through a parking space so the nose of the car is headed out, if at all possible.