We ate at Margarittaville last week and my kids absolutely loved it. There were people on stilts walking around making balloon hats for all the kids. The food was really good too. All my kids had the chicken fingers and fries and my husband has the coconut shrimp and I had a seafood pasta. We got there right at 5pm and didn't have a wait. When were leaving though I heard someone say the wait was an hour. My kids got inexpensive souvinears in the gift shop downstairs. The kids menus are parrothead masks and my kids got a kick out of that too! This will definately be a regular place we will stop at.
My kids, 14 & 10. loved the Hard Rock Cafe. They have a great kids menu and while we were there the waitress/waiters danced to YMCA standing on chairs...it was alot of fun.
Tchoup Choup is a bit stuffy -- though, like Emeril's and Hard Rock's Palm -- there is nothing wrong with taking your kids. If you go during the week (rather than the weekend) when the place doesn't fill up as quickly and your service will be faster there's no harm in giving it a try.
Great place, though not as kid-friendly as the restaurants in the parks or most of the places in Citywalk. Right near the Tchoup, at the Islands dining room they do have a kid's buffet. But I don't blame you for wanting to check out Tchoup. It's pricey but good.