Hi
Erika!
Congratulations on your family's visit to the Walt Disney World Resort!
You may experience obstructed viewing of IllumiNations: Reflections of Earth from the beach at Disney's Caribbean Beach Resort. Try either Trinidad South or Martinique. There are some spots on the beach offering partial views of the upper level fireworks and lasers of IllumiNations. However, if you choose this option, you will miss a great deal of the pyrotechnics, music, and choreography of the Epcot fireworks. In order to avoid any disappointment on your part, I would recommend viewing IllumiNations inside Epcot.
As far as "must dos and sees" at Disney's Caribbean Beach Resort, I would say don't miss the main swashbuckling themed pool, Old Port Royale. It boasts two water slides; one of which zips through the inside of the fort! Also both
Old Port Royale Food Court and
Shutters at Old Port Royale are excellent dining venues which shouldn't be missed.
Please let me know if I can answer any other Disney Vacation planning questions for you. It would be my pleasure to help you plan a most magical visit to the Walt Disney World Resort for your family!