Disney Cruise Help please!!!!?

Ok I have a few questions. Last year when I went on a Disney Cruise they had christmas ornaments for sale (they also had christmas decor up). This time we are going a week earlier and the Christmas Decor wont be up. My mom's b-day is a week later and I wanted to get her a christmas ornament but Idk if they'll be selling them. When do they start selling them??? Next question. I was looking at Royal Caribbean's website and I saw Cococay and Labadee. What are those? Next Question. What all is there to do at castaway cay (i know most but can't remember all.) Thank You so Much!!!!!!!!!!