Are you going to the Resort shared by Worldmark and Worldmark South Pacific? We were there several years ago. We did several all day snorkling trips. We ziplined. We did an all day tour that included the Orchid Garden started by Raymond Burr, a Fiji Village, and the Hindu Temple. Remember to dress appropriately for the Hindu Temple. They will loan you srongs/wraps to put on if you are not dressed appropriately.
We also spend several days laying around the Resort and enjoying the Pool/Swim up Bar.