We just came back last week from RPR. There is a shuttle for Sea World. I am not sure about Wet n' Wild. I think I asked and they said there was, but the lines looked pretty long and the kids loved the RPR pool. The Sea World shuttle leaves at 9 and 9:30am(or 10 and 10:30) I believe and has ONE return time. I believe it was after dinner time. We opted for a Taxi at about $12.00 each way. I didn't think we would stay all day and we wanted to be back for dinner at Citywalk that night.
Good Luck and have a blast at the awesome RPR!!!
-cortegro