Pound for pound, the Beach Club is my pick for the best resort on the entire WDW property.
Accomodations: The rooms, hallways, lobby are all beautiful in every aspect, from furniture to color patterns, etc.
Park Access: Like the Boardwalk and Swan/Dolphin, staying at the Beach Club affords you about the largest number of transportation options you're going to find at Disney. You can walk to MGM or Epcot, take a bus to Animal Kingdom, Magic Kingdom, Downtown Disney, and all the water parks. You can even combine options: I've gone so far as to walk over to Epcot, head straight through the park to the monorail station at the front, then hop on the monorail and switch trains at the TTC and head to Magic Kingdom!
Food: The restaurants at the Yacht and Beach Club are all well up to Deluxe Resort standards; very elegant and yet comfortably casual. Not being a big fan of more luxurious restaurants, however, I tend to head for Beaches and Cream, the 50s-esque soda shop/burger joint near the pool area. You can sit down at a table or booth, or get your food to go, which is a nice option. The only part I'm not sure on is the refillable mug issue, since I don't usually bother with them.
Pool: Tramp nailed it: the best pool on property. The pool itself is a sand-bottomed lagoon that winds its way around a huge parcel of land, under walkways and bridges, and features a nicely secluded hot tub and plenty of sunbathing room. The waterslide is huge. Starting from the broken mast of a shipwrecked boat resting on the beach, you slide straight down a tube for a good thirty-fifty feet, then shoot out into a few tropical twists before splashing down in the lagoon pool. Trust me, it rocks.