Hi Kathleen!
Thank you for your great question and for allowing the Disney Parks Moms Panel to assist in your vacation planning!
I absolutely love Disney's Caribbean Beach Resort. My family enjoys trying out new resorts on each trip, but we always find ourselves returning there. It is true that you are able to see some of the mid-air fireworks from Epcot's IllumiNations: Reflections of Earth. This is a nightly show, which is ususally performed at 9:00 PM. (Subject to cancellation) You will also be able to hear the noises associated with the fireworks. One of my kid's favorite things to do on our early nights, is to get ready for bed, put their pajamas on, and then go outside and watch the fireworks from one of the many benches around Barefoot Bay. When it is over, they brush their teeth and jump into bed! It is a great ending to a magical day. Other than the firework noise, I have never found the Caribbean Beach Resort to be very noisy. The Disney Resorts do implement a "quiet time" between 10:00 PM and 8:00 AM and we have always slept wonderfully.
If you are still concerned about the noise from the fireworks,
Disney's Animal Kingdom Lodge sits furthest away from any of the theme parks in order to not spook the animals. The rooms here are lovely and we really enjoy all of the dining options.
Have a wonderful trip and enjoy your magical vacation!
Pixie-Dusted Wishes,
Lauren