Hmmm, the answer depends on what you really are: adventurous or luxury junkie - can't be both
Since you have no pricing restrictions and looking more for luxuries than to get the taste of real Thailand, Phuket is the best place to be. I can't comment on the best resort, since I haven't tried any of it (I can't afford it). What sort of "things" do you want to see and do at night? For nightlife - Patong. Although I am not sure if any upscale accommodations are in the area.
I'd wait to get there to plan the activities as you will have so many to choose from. Don't worry, folks there love people without pricing restrictions and won't refuse your money; you could get virtually anything
I assume that you won't be very happy spending much time on boats, so I wouldn't recommend island hopping, but one day trip to Phi Phi is a must