We stayed at the Dolphin when we only had 3 days in the park. Swan/Dolphin is right between the Yacht Club and the Boardwalk, it has all the same location advantages of those resorts but it was much less expensive. S/D is not owned by Disney, but is on Disney property. The bus service to MK was very good. We liked the idea of walking through Epcot and getting on the monorail, but never had time to do so.
The Epcot area resorts allow such quick access to two parks, and nice perks with the Boardwalk and other resort restaurants being so close by. We went to MK and MGM twice during our trip, and to Epcot and AK once. We also took a pool/nap break each afternoon. Since we only had 3 days, I wish we would have skipped AK and spent more time at Epcot.