I would suggest Discovery Cove if you havent been before, definitely a treat for everyone.
We went hot air ballooning for my husbands 40th and would recommend it. Our boys were 6 & 8 and they helped unfold and inflate the balloon and attach the basket. The flight was about an hour and we had a champagne breakfast when we landed. As it is an early morning activity we then had the rest of the day to celebrate, we went to Beaches and Cream for a kitchen sink dessert and then later in the evening a meal before rounding off the day with Wishes fireworks.
We would also recommend Daytona Race track if your DH is into race cars, we took a tour of the circuit and then finished off with a few hours at the beach.
Could you look at the Disney tours ( some have age restrictions)