Here's my thoughts,
Character breakfast - Chef Mickey at CR, Tusker House at AK, Crystal Palace at MK
Character Dinner - Tusker House at AK - Garden Grill at Epcot - Hollywood and Vine DHS
Epcot -
Corral Reef - this is a nice relaxing spot to enjoy dinner, with a wonderful view into the "Living Seas" the all the seating is stadium style facing the under the sea life, so all seat are great... the kids will love all the fishes, sharks, turtles... We have eaten here several times with our grandson, around the same age as your boys... he loves it... food and service have always been on point for us...
Teppan Edo in Japan is another action dinning location... and the kids love it... Food and Service are spot on... from start to finish...
Magic Kingdom
The Plaza - We like to have lunch here, they serve sandwiches, and really good milk shakes... its a nice break from the parks without leaving the park
BOG - for dinner so that they can meet the Beast... We haven't been since they changed the menu.. it's really something inside, you feel like your in the movie...
Animal Kingdom -
Rainforest Cafe which there is one on site at AK, is a great spot to have lunch or dinner...as well they serve breakfast( only at the AK location) while not character it is well themed, and super fun... You can enter from either outside or inside the park...Portions are quite large here...
Yak & Yeti - It's been a while since we dined here, and it has a large menu... and we 2 people with food allergies, which they accommodated with no problem, the noodles were really good.
Hollywood Studios
SCI- FI - super fun eating in the car, and the B rated movies... Hamburgers, Sandwiches, and another spot for really good milk shakes...
Mama Melrose's - food and service have been on point each visit, DH really enjoys the Chicken parm... and I like the Shrimp and pasta dish...
Disney Springs
Rainforest Cafe and T-Rex Cafe - is our grandson's favorite place to eat, he loves all the dino's at T-REX... he is Dino crazy he will be 4 at the end of this month... everything is about dino's...
There are so many new options at Disney Springs... to choose from...
As a suggestion spend some time really checking out the menus... Make your ADR's so you can get what you want...