The one that immediately comes to mind is Tusker House Breakfast - yumm and lots of options for food
Also Boma, Cape May and Chef Mickeys for Breakfast
We've done 1900 Park Faire for Breakfast and dinner - selection is good but it depends on your kids tastes. The food to me (other than the kid section - mac/ cheese, pizza etc) aims a bit more towards adults so it's more hit/ miss for kids IMO.
At Akershus in Norway (for all meals) they say they have a buffet but it's not impressive. Mainly you're ordering off the menu and you can visit the buffet which is things like fruit, cheeses, pastries/ danishes (breakfast) and cold cuts. Not really a 'wow' IMO