Hi, Bridgette! Walt Disney World is situated in Central Florida, and the closest beach where you can see the ocean is about an hour away from the Walt Disney World theme parks. While I don't have any information about glass bottom boat tours, you definitely don't want to miss the Living Seas at EPCOT! You'll get up close and personal to many of the sea creatures you might find off the coast of Florida, with some great information about the ecosystems these animals live in.
You might also want to consider a behind the scenes tours, such as EPCOT Seas Aqua Tour, which gives you the opportunity to snorkel in a tank of more than 6,000 sea creatures. No glass at all between you and these gorgeous animals - well, except what's in your snorkel mask!
More information on this type of behind the scenes experience can be found by clicking
EPCOT Seas Aqua Tour.
Happy planning, Bridgette!