You are a little confused on terminology.
WDW is all of WDW - 50 some square miles. As the resort restaurants are in WDW, they are all convienient to WDW.
The parks:
MK - Magic Kingdom - the monorail restaurants will be the most convienient to MK - Chef Mickey's will only take about ten minutes to get to from the front of the MK and is a great choice for a late breakfast. Kona Cafe at the Poly for Tonga Toast. Dinner at Ohana or Narcoosees......
Epcot and MGM - the BW area restaurants are the ones conveinent to these parks, these restaurants are in the Boardwalk, Yacht and Beach Club, or Swan and Dolphin hotels. Epcot is a pretty large park, the Y&BC is only about five minutes out the International Gateway (and the other resorts only a little further), but the IG may be quite a hike if you are at Mission Space. The resort are a little farther from MGM, but still manageable - and there is a boat that goes between Epcot and MGM, stopping at the resorts.
AK - the AKL (Animal Kingdom Lodge) is really not very convienent to the AK itself, and there aren't many resorts that are. But a short bus ride would take you to the AKL, where Boma servers a breakfast and dinner that most people here rave about.
With 50 square miles of property, it generally isn't convienent to bop from the MK to AKL for dinner, or from MGM to Chef Mickey's. But people do and it can be done.