Saratoga Springs.
Boat from the main building.
Bus from several points throughout the resort.
Walk from (I think) the Congress Park section (request "close to Downtown Disney")
Next choices:
Port Orleans French Quarter (boat/bus - bus stops here first, boat stops to/from POR)
Port Orleans Riverside (boat/bus - boat stops here first)
Old Key West (boat/bus)
Pop Century (bus not shared with any other resort)
Coronado Springs (bus not shared with any other resort)