another vote for the 4 day park hopper pass.
We have found that its a really good idea to spend one whole day at the water parks just to relax and veg from all the running around you do in the parks. We take our "beach day" in the middle of our stay.
Totally agree that the better restaurants are in the World Showcase at Epcot.
There is however a really good seafood restaurant right on the water over at the Marketplace, can't remember the name right now. You have to make your reservations early at all the restaurants if you want to get in at a time you want.
If they still do the Laser light show at Epcot thats a must see.