First movie my wife and I saw after having our first kid was the first Captain America. There was a family a row or two ahead of us with a little boy that really kicked the viewing experience up a notch. I'm sincere about that. He reacted to everything with such extreme emotion it made things way more fun.
The best part was when Cap goes out on his own to rescue the guys. When they walk back into the camp the kid jumped on his chair, pumped his fist and yelled "Yeah! He did it! He saved them! He's a hero!" or something like that, I don't remember exactly. Everybody laughed because it was what we were all thinking, but had been conditioned to not react with such an outburst. I loved it. That kid ruled.
I'm saying this because if you run into a family at the Joker with a kid that's reacting emotionally to everything you're seeing on screen GET THE HELL OUTTA THERE.