Our personal favorites that would be good for a younger child as part of your group are:
Garden Grill - Epcot, in The Land. Character Dining, lots of choices and plenty of food. Expensive but definitely worth it once. The restaurant revolves slowly around the ride and is quite relaxing yet engaging and the food is fabulous.
Biergarten - Having grown up eating German food and seeing German entertainment (including in Germany) I can promise you this is not "theme park" German food. Authentic and pretty close to my Oma's cooking. The entertainment is sure to keep the 4 year old occupied as well, lots of fun here!
Whispering Canyon Cafe - At the Wilderness Lodge. Lively atmosphere and definitely excellent for kids, they even have stick pony conga lines through the restaurant. My DH is involved with competition BBQ so he's very picky when it comes to BBQ and even he likes the food here. Ask for ketchup for real fun. After dinner take a walk in the back by the pool to see "old faithful", then hop a boat back to MK to go home.
Sci-Fi Dine in - Studios. Dining in the dark in a sort of car, at a drive in. My kids loved it when they were younger, and continue to enjoy it as teens. Make sure to get a light-up drink! You get to keep the novelty "ice cube" to have fun with later.
Raglan Road - Disney Springs (aka Marketplace) Really nice pub atmosphere. Irish fare and Irish dancing. Relaxed and fun.
T-Rex - Disney Springs. Fun. By Rainforest Cafe but specifically for Disney, so it's like Rainforest on steroids. LOL
For fast food we love Peco Bills in MK, nothing so special about it but the food is basic and good and the atmosphere is just fun.
Boatwrights - at Port Orleans Riverside, makes for a nice evening out away from the parks. Food is great, and if you plan it right you can see Yehaa Bob Jackson at the River Roost Lounge, and then walk around by the marina- it's a lovely resort.
Cape May Seafood Buffet - Beach Club Resort. Great seafood and fun, lively atmosphere but not too crazy. Another great place to walk around, hop on over the the boardwalk. If you don't like seafood though, don't bother!
Those are our favorites for you. I have "honorable mentions" too; Yachtsman Steakhouse at Yacht Club serves some of the best steaks we've had and we live close to NYC so we've been to some of the best steakhouses around. Boma is simply fabulous with something for everyone and the AK resort is also great to walk around but neither of those two are particularly good for younger kids.
Hope that helps in some way.
