The Beach Club is a lovely resort, and it hands-down has the best pool. With that said, we still prefer the Polynesian because of its easy access to the parks & beautiful gardens. A short monorail or boat ride takes us right to the Magic Kingdom. After a quick walk to the Ticket & Transportation Center, we can catch the monorail to Epcot. The other two parks, however, are by bus.
We find the Polynesian to be in the center of activity while still being peaceful & relaxing. Walking through the gardens, especially when lit by torches at night, a beautiful treat. The resort runs along the shore of the Seven Seas Lagoon where we enjoy having the option of watching the fireworks away from the crowds.
There are two pools at the resort: a themed pool and a quiet pool; there is not a jacuzzi. The themed pool has zero-entry, plays music underwater, has a splash area, and large volcano/water slide. Throughout the day, there are an assortment of activities that do vary: water noodle games, water basketball, arts & crafts, campfire sing-along, etc.
If you'd like to read more about the Polynesian, I'd suggest looking at www.tikimanpages.com It is a website devoted to everything and anything you'd like to know about the resort along with extensive pictures.