We were there a couple of weeks ago. Our favorite was Le Cellier for the food, service, and atmosphere (in that order). Can't tell you if how great it is for kids...our 3yr old actually fell asleep in the stroller right before our ADR time and they let us push it right up to the table. He slept through the entire meal (the was
after our mid-day break at the hotel during which time he refused to fall asleep [sigh]). Anyhoo... the kids desserts were really great looking. I almost wanted to order one, lol. Last minute ADR's for Le Cellier are probably hard to come by but definitely give it a try if you're interested, you never know. If you're flexible with your time you might get lucky.
Our 2nd favorite was the Coral Reef. We enjoyed our meals, the chocolate lava cake (I think that's what it was called) was to die for! So yummy.

I loved looking at the aquarium and seeing Mickey swim by (what a surprise). The only downside to this restaurant IMO was the noise level. It was extremely loud in there. Probably due to the massive number of children and also the fact it has an amphitheatre design. Even so, we will definitely go again someday.
Btw,
www.allearsnet.com has menus of the restaurants in the Dining section. Check those out if you're wondering what kind of food is being served, especially if your kids are at all picky as the children's menus vary.
hth.