I third the recommendation to watch it on
Youtube (or similar) and then see how your daughter reacts. Remember, F! will be more intense in person because the sounds are louder, it's dark outside, things are bigger, etc. I agree that the dragon is probably the scariest part, but there are also very large mist screen projections of several villains (complete with intense/ominous music) that might also scare children. I do know that some folks have reported back that there children were scared, while others said it was fine, so it really varies by child.