We had a long layover in FLL last year and took a cab to a movie theater. It was in a shopping plaza with a TGIFridays for lunch. We asked a clerk in one of the airport stores for theater information. You could also look into taking the FLL water taxi. You buy a ticket that is good for the whole day and can get on and off where you please. The beach is about a $14 cab ride from the airport, but I don't know much more than that. Have fun!