We went to Universal Studios for our excursion. As mentioned above, if we were able to leave a 10am or get back later, it would have been more fun. We felt very rushed and had to do the whole park in 6 hours. I highly recommend getting an Express Pass for Universal as it allowed us to get on every ride at least once without having to wait in line. I dont think that the Harry Potter attractions in Islands of Adventure accepted these but it worked fine in the park that we were in. Probably the best investment we made on the trip. If not, we probably would have been able to do 4 maybe 5 rides.
we went to Atlantis and did the AquaAdventure and the DOlphin shallow water encounter. Totally worth it. Again, would have been nice to have 2-3 more hours to explore the aquariums and the rest of Atlantis....it is huge. Transportation to and from was about 10 minutes. Dolphin encounter was excellent but be willing to pay if you want pictures of your experience. The cheapest package was about 60 dollars.