My DH and I stayed at the Dolphin for our honeymoon in 12/99. It was his first time to WDW and he loved it! I think the best part is the close location to EPCOT's International Gateway and MGM. Plus, we'd take a walk to the Boardwalk or the Yacht/Beach Clubs for extra dining options and entertainment!
We also had a great room with a balcony facing EPCOT, we could watch the fireworks from our room everynight, with an awesome, unobstructed view.
It is themed differently from the Disney Resorts and you can't charge on your room key in the Parks (at least we couldn't when we stayed there). But, I would stay at the Dolphin again!