I absolutely hate the idea of waiting an hour plus for a 25 minute show. So, let me chime in here with our experience. We are a family of 4 and have never shown up more than about 20 minutes early. We have been there three times and have sat all over the stadium. There is not a bad seat in the whole place. The first time we were on the side and it was fine. The second time we went right down the middle and filled in a spot of empty bench. This last time crowds were low due to rain and we were able to get great seats in the middle. Again, there are no bad seats in the theatre. That said, I haven't been at peak times and that may make a difference. Remember, you can always do the fantasmic package and they reserve a seat for you.
Regardless, this is a great show. You won't be disappointed.