Either resort is a good choice. We've stayed at the Dolphin 4 times now, and will be staying at the Swan for the second time in February just DH and myself. The kids are staying home, woo hoo!
The Dolphin is bright, festive and bustling with people.
The Swan is elegant and more subdued.
Both are basically in the same location. The entrance to the Boardwalk is a little closer from the Swan.
The main Grotto pool
seems closer to the Dolphin. Both have their own lap pools.
The Swan has what is called a "hollywood bath" meaning there is a sink in with the tub and toilet, and another sink right outside the bathroom door. The Dolphin just has the one sink.
Both have the wonderful
Heavenly Beds that are the most comfortable hotel bed I've ever slept in!
The Dolphin has the convenience of Tubbi's Buffeteria, a 24 hour eatery as well as the cute Dolphin Fountain. The Dolphin also has an arcade and laundry room.
Both resorts have some of the best views on property, IMHO.
Have fun deciding!