I would strongly suggest Hoop de do Review for all ages.
Check out park listing for rides and restaurants here on this site and on
www.allearsnet.com.
For your meals, you will need reservations.
I think it would be a good idea to get a guidebook to look over before hand. I suggest the Unofficial Guide.
It will be a bigger challenge staying off site with the little ones, but I would focus on mornings and coast for afternoons so as not to totally tire them (and you)
At AK
Don't miss Festival of the Lion King, possibly the best show in WDW
Safari is great for all (do it early AM)
Expedition Everest for all tall enough
Dinosaur may be too intense for all three younger ones
Flights of Wonder would be a good show to relax at in the PM with little legs getting tired.
Tough to Be a Bug (in the Tree of Life)
...maybe Kali River Rapids...but chances are you will get soaked!
For MGM
Check into dinner packages that include special admission to Fantasmic. With the small children having reserved seats and less time to wait are the way to go.
50's Prime Time Cafe for dinner...you will really enjoy it, and the kids will like mom and dad getting picked on.
..also Sci Fi Drive In (best for lunch)
All will like both Indiana Jones Stunt Show and Lights Motors, Action Show (get fast pass for that)
If you're short on time, skip the backlot tour, it isn't near what it used to be and except for a few parts, the younger ones will be bored.
Epcot
All the countries have good restaurants, up to your taste
All will like Soarin' and Test Track (hopefully meet height requirements) [take advantage of fast pass for both]
Mission Space may be too intense for this trip
Illuminations fireworks
MK
Well there's lot of rides....
Lunch or Dinner at the Castle (dinner is easies for Res.)
Liberty Tree Tavern is probably the least crowded character meal (dinner only)
Parade and Wishes fireworks
Depending on time, you may also consider the Boma Dinner buffet at AKL, O'hana at Polynesian, Whispering Canyon Cafe in Wilderness lodge. These all have a wonderful exotic feeling and are very kid friendly but pleasant for adults as well.