Crystal Palace, Chef Mickey's, Biergarten...we went to all of those and they are loud restaurants and perfect for kids, in my opinion. Also, they are buffets so you can make the meal very quick. We were out of each one in an hour or less and did not feel like we rushed it at all. Our kids loved the characters, and they do things where the kids can participate so your little one can stay active at times during the meal. Biergarten had a dance floor and there were a few kids out there dancing. It was excellent food and entertainment and we plan to go back there next summer!
You could also try non-character restaurants that are more active and loud...Ohana, Cape May Cafe (it's a buffet so you can get out quickly if necessary), Whispering Canyon Cafe. Boma is also a good buffet but less active.