I know someone who did dolphin quest and really loved it.
I pulled this from this site (wdwinfo.com)
Dolphins in Depth: Here's your chance to get up close and personal with a live Dolphin. Explore the backstage areas where these amazing mammals are cared for and learn more about the research being done at Epcot's Living Seas pavilion. You are required to wear a bathing suit. Wetsuits are provided for the water part .Discounts available are DVC, Annual Passholders, The Disney Club, Military,
AAA Diamond Card. For more information and reservations call (407) WDW-TOUR (407) 939-8687. All prices include tax. Program itinerary, content and prices are subject to change without notice. Program may be subject to cancellation to meet the dolphin's needs.
I hope this helps. Another thing you should know about is the snorkeling at Typhoon lagoon. It's really cool. It's a man made reef with tons of fish and SHARKS! The sharks are fairly small, not aggressive and, I assume, very well fed before the snorkelers come in. I've done this and it was really great. It's included with your admission to typhoon lagoon.
Chris