Elizabeth, since you are right at Epcot's "back door" you'll probably want to spend NYE there. Well, as long as you last with a 5 yo that is! They have some family dance parties near the fountain, and parties for a slightly older crowd in Japan, etc. There's an incredible fire work display at midnight that you might be able to see from your room. The best thing is, you won't have to wait for buses on that very busy night, it's a very short walk. Enjoy!