it a short drive to all the parks from Reunion (if you leave Reunion passing the waterpark, you will see a new toll road to your right that takes you right onto the I4 - it costs 25 cents), you can be at the entrance to Disney in about 10 mins, Sea World is approx 20 mins.
I personally would not stay anywhere else, there is nothing to compare to Reunion, it is fabulous.
Karen