You are going to get answers all over the place on this one! For pure Disney magic, all of the resorts on the monorial are the best to me. They are the farthest away from real civilization, but right in the heart of the action. All three have great pools and marinas with a large boating playground, all three feature some of the best restaurants at Disney, all three are very convenient to MK and Epcot, all three feature rooms larger than the standad deluxe room, all three have exceptional concierge lounges (if that interests you), all three allow for excellent views of FIS fireworks, maybe even from your room, all three have nightly presentations of the EWP, all three have easy access to Fort Wilderness and the activities there (including the Hoop-dee-doo Revue), also in addition to the monorial all three feature boat and bus transportation. They, of course have some drawbacks (it's difficult to get to the boardwalk at night, MGM and AK share a lot of stops and make the bus trip pretty long), but for pure Disney magic, these three are the best the Mouse has to offer, IMHO.
All of that being said, perhaps the best themed resort anywhere is the Animal Kingdom Lodge (with Wilderness Lodge right on its coat tails). It really transports you. It is like a vacation within a vacation to stay there.