When we first started to go to WDW, when my kids were little, there were no FP lines, etc, so the queues were long. We played guessing games, counted, talked about what we had already seen or might do that day, etc.
Age 0-5 is the time the brain is doing most of the hard wiring for learning - if you can avoid using electronics to pacify your toddlers, you may end up with smarter ones, IMO! Or ones without ADD, anyways.