We really like Flametree BBQ, too, and since you will be there in March, sitting outside shouldn't be prohibitive by the heat.
Our other favorite is Tusker House. Their food is YUMMY! The kids menu is really good, and you can eat inside, out of the weather, or take the food outside and people watch while you eat. Many times they have the African entertainers out there, which are great for not only the kids but the adults, too!
As for Restaurantosaurus, it is like a glorified McDonald's, which is fine, if that is what you are looking for. Personally, I give the edge to Tusker House for variety, seating and entertainment value!