My husband, eight year old son and I have decided to take our summer trip to Yellowstone. We have SW airline vouchers and want to use them to get as far as we can...Salt Lake, Denver?? and then rent a car and drive the rest of the way. That said, can anyone tell me which entrance we should look at staying at during our visit? And Why? I have heard a lot about the north entrance and things to do. Also, not sure what route to drive there from these airports??