From the Dolphin, you can easily walk into Epcot or DHS.
It's about a 10-15 minute drive to either Epcot or DHS from Caribe Royale.
If you are driving to MK or AK, the drive time is about the same from either the Dolphin or Caribe Royale. I would guess, 20-30 minutes.
I noticed that you mentioned breakfast is included?
Are you sure you're not thinking of Buena Vista Suites, next door?
Unless you have a special deal lined up, Caribe Royale doesn't normally include breakfast, but Buena Vista Suites always does.
I love staying at the Dolphin, the location is awesome.
And, of course, you can take the frequent bus service to AK or MK and walk or boat to Epcot or DHS.
But, on the other hand, the money saved by staying at Caribe Royale is huge.
You will need a car, the busses are few and they drop you far away.