I agree with MouseTyme, the regular dining plan is usually more than sufficient and you can work it to get more than your money's worth out of it!!
As for as a "park plan" ...
EARLY MAGIC HOURS - if you are staying on property, take advantage of the Extra Magic Hours (before park opening or after park closing) ... but one tip, when doing the MORNING extra magic hours at Magic Kingdom, once the park opens to the public we tend to park-hop to another park (MK appears to be more crowded on the days that they have the morning EMHs). EMH is a great opprotunity to get the "popular" attractions done, usually without bad waits. That then frees up the "public hours" for other attractions, and letting the off property folks suffer the long lines at the more popular attractions.
PLAN AHEAD ... go over the park maps, decide what you "must" do/see versus what can be skipped (without any broken hearts) if you run out of time ... create a skeleton of a plan of attack ... you don't have to go commando and know down to the second what time you'll hit each ride (some people do that, I know), but plan on going counter-clockwise (most people tend to go clock-wise), do everything in one area before moving onto the next area ... don't waste a lot of time criss-crossng back and forth all day.
One exception to counter-clockwise ... Animal Kingdom ... we beeline for the Safari ride first thing in the morning, where your chances of spotting animals is better (in the hot afternoon they tend to disappear/go to sleep, making the ride "eh") ... so that's a park we actually do in a clock-wise fashion.
START EARLY - be at parks before the scheduled opening time - if a park opens at 8am, try to be there around 7:30am - there have been occasions where they'll open a few minutes early (for example Magic Kingdom might let you into the Main Street area pre-opeening, and you can be at the end of Main Street when the rest of the park opens).
USE FASTPASS whenever you can ... get the FastPass, figure out how much time you have "to kill", do some other attractions in the same general area, then go back and use the FastPass ... then move onto the next attraction where you can get a FastPass. Test the FP system, some times (not always) SOME attractions will let you get a FastPass if you are already holding one for another ride. This does not always work, but sometimes it does and is worth taking advantage of when it works out this way.
TAKE MID-DAY BREAKS!!! Running yourself ragged doesn't pay off - especially if you have kids - there's nothing like that 3pm toddler (or teenage) tantrum because they're exhausted. Take a break. This can be a trip back to the hotel for a nap, swim in the pool, or a trip to one of the water parks. Sometimes it's something as simple as planning lunch at a sit-down restaurant.
GET PRIORITY SEATING - whenever possible plan your meals in advance and get priority seating for sit-down restuarants - if you think standing in line for a ride sucks, waiting at a restaurant for a table is worse.
PARK HOP - we'll do AK in the morning be done there by (or shortly after) lunch, and then spend the rest of the day at one of the other parks. We'll especially do AK when it's got EMH in the morning, and then if another park has EMH that night, that's where we'll end our day.