We stayed at the Fairfield Inn and it was a 5 minute drive to Sea World, Aquadica and Discovery Cove. It is a preferred Sea World hotel, so free shuttle and early admission and free quick que passes. If you like a suite, the Staybridge, on the same property, is also a preferred. Check out the Sea World website, they list all the preferred hotels.
One thing I will mention though. The Fairfield said it was across the street from Sea World. While it was across the one side of Sea Word, and you could see the one rollercoaster, the entrance was down the street from the hotel on the Parkway. The hotel is just south of the International Drive/Parkway intersection. I did see people walking on the Parkway near the hotel, but I never tried. Very, very scary! Not all sidewalks and fast traffic.