It certainly all depends on your family's particular eating preferences, but as others said, the DDP offers the least value at breakfast. As a result, when we're using it (that is, when it's free or we otherwise have a compelling reason to use it, as it's tough for us to save much with it), we use the CS credit for lunch and TS for dinner, and have a quick breakfast in the our room of cereal or granola bars and coffee from the in-room coffeemaker.
If you do plan to use your CS credits for breakfast and TS for dinner, I would suggest skipping lunch, having breakfast a little late (definitely use one of those CS credits for breakfast at Be Our Guest, if you can get an ADR there, especially if it's pre rop-drop so you get first crack at 7DMT!) and scheduling your dinners a little early (e.g., 4:30pm) and making your dinner ADRs at 1-credit buffets and 1-credit all-you-care-to-enjoy family-style venues, so you can get the most bang for your buck by skipping lunch and filling up at dinnertime. (Some good values for 1 credit include Crystal Palace at MK, 'Ohana at the Polynesian, Boma: Flavors of Africa at AKL, Tusker House at AK, Liberty Tree Tavern at MK, Biergarten at Epcot, Akershus at Epcot, Garden Grill at Epcot, etc....)
I agree with everyone... use your dining plan wisely on table service meals, especially character meals ( even breakfast buffets) and also eat at quick service restaurants that would be a bit more pricey but are still on the dining plan ( we do that for snacks too). Just check out the menus.
