I've stayed at Grosvenor, Doubletree Suites and the Hilton.
The Hilton by far had the best pool area. There are two large pools and hot tub. Gazebo. Landscaping. Lots of seating with padded cushions on them, some with umbrellas and small tables. Didn't have that concrete rectangle feel to it.
Doubletree was nice on a small scale, but the noise from I-4 was bothersome to me.
Buena Vista Palace has a great pool/recreation area. This resort probably has the best public areas of the DTD hotels. It is very secluded and spread out over 27 acres.