My son will be just under 2 when we go. I am on the deluxe dining plan and expect to share with him at most, if not all meals.
I made quite a few reservations at character meals for my son - also they are usually buffet or family style so it will be easy for him to share.
If you're considering the dinning plan - with 4 children under 3 you might consider this - the Deluxe Dining Plan (that's what I'm doing). The deluxe plan is about $32 more per person per night, BUT it includes 3 meals a day (instead of 2) and they can be either table service or counter service (your choice)- the meals include appetizer, entree, dessert and soft drink (regular plan is only entree and dessert) and 2 snacks a day for each person (the regular plan is only 1).
With all that food there will definately be plenty for all of you without having to order more. Sometimes appetizers are big enough to be a meal themselves and may be perfect for the kids. And with 4 snacks a day between both of you that's more than enough to share with the kids. Check one of the sticky threads in this forum for all the places you can go for snacks and all the different ones you can get - it's not just ice cream & popcorn.
Also it will allow to book more character meals since you can do TS or CS on deluxe plan. Not only are the character meals buffets, I think it's a great way to help keep 4 young children occupied in a restaurant.
The deluxe plan offers you the flexability of Counter Service or Table service and though it's a considerable amount more, with 4 little ones under 3 it may be worth it. Depending upon what type of eaters your kids are it may be hard to share 2 entrees with 2 adults and 4 kids (what you get on
DDP).
I also plan on bringing my son's favorite snacks. If you're flying you may want to ship some of these supplies to the hotel beforehand. I plan on having diapers and drinks and his snacks delivered to the hotel so I won't have to lug all that stuff on a plane. You can either ship it from home via UPS ground or order online from a grocery service (the one in Orlando is Green Grocer I beleive) and they will deliver to your hotel.
Good luck - sounds like a fun and busy time with 4 little ones under 3.