Staying in a condo can be a real budget saver for you. We stay at Bonnet Creek b/c my folks are Wyndham owners and they gift us a week when we head to Orlando. We are able to have a heavy-ish breakfast and then we can either share CS (2-3 meals for 4 of us, depending on the place) or just snack in the parks around lunch time. We don't like to take in anything big, but I would think you all could carry a hefty snack in a couple of backpacks or small coolers. Backpacking snacks are generally lightweight and calorie dense - my boys like pb or nutella on tortillas, pepperoni with crackers, granola bars, pb crackers. Store brand crystal light packs make water more exciting and are frequently very inexpensive (also try Big Lots for these). Then we make dinner at the condo and spend the evening with Redbox movies or in the lazy river.
Alternatively, you could make a heavy breakfast, take light snacks to the park, and come back for pool time and a big meal around 3, then back to the parks for the evening. Either way, if you can just do 2 good sized meals at the condo, you can get away with snacks only the rest of the day.
We buy most of our food at
Walmart after we arrive. We also rent Redbox movies there. Easy and filling meals include crockpot meatballs (bring your own crockpot) with couscous or as sandwiches; spaghetti; frozen chicken patty sandwiches with frozen fries (bring or buy cheap / disposable jelly roll pans, as most units only have one); hamburgers with chips; hot dogs or polish sausages on buns with baked beans. I generally bring / buy disposable muffin tins and some 69cent mixes to make snacks, and you can also do microwave popcorn in the microwave at the units.
The condos also make non-park days fun. Bonnet Creek has 2 lazy rivers, several pools, mini-golf, and other activities. I would assume any condo / apt rental would at least have the full kitchen, pool access and a dvr.