Hi Melisa,
If you are staying at the HRH at the beginning of your trip, and planning on doing Sea World, stay at a hotel close to Sea World for your last 2 nights. The Renaissance looks nice, it's located behind Sea World. Do a search to see if you can find any more info on that hotel. (You may not like any place as well as HRH...)
Anyway, Sea World was really great. Just one thing to remember: You will not wait in any line while at IOA/Universal. You will have to wait in lines at Sea World. But, if you have 2 days to tour Sea World, you will be able to do it all. Have fun!