I would definitely say the 1900 Park Fare dinner! They have Cinderella, Prince Charming, Lady Tremaine, and the evil stepsisters Anastasia and Drizella! They all get into character and the stepsisters yell at each other and tattle on Cinderella to their mom. When I was there one of them came to our table and pretended to pass us by and said to me "UGH!! ANOTHER BLONDE!" It was SO funny!
Another place that is really lively during the earlier dinner hours is Ohana. I don't have little kids in my party (I'm in college and usually go with friends, parents, or siblings) but they have a Hawaiian singer playing a uekelele and playing games with the kids, doing parades, teaching them dances, etc. The later your reservation, the fewer kids will be there and she just plays music which is nice. They also dim the lights and pipe in the music to Wishes, which you can see if you have a table by the window! It's actually my favorite dinner on property!