In this film, the toys' person (Andy) has grown up and is headed off to college. What will happen to the toys? Will they go to the attic? Be donated? Get trashed? Turns out it's a little of all three, but their ultimate fate is much more satisfying, if teary-eyed. It's an excellent family film.
My only reservation about the Toy Story franchise is that the basic premise (that toys can be sentient and have emotional attachments) promotes Disney's basic goal (to sell new merchandise). I could imagine small children, after seeing these films, having greater difficulty than they already do parting with unwanted toys, and this particular film does not paint a favorable portrait of donation. For small children, children who have difficulty distinguishing fantasy and reality, or children who easily for emotional bonds with inanimate objects, I would exercise caution with this film. Perhaps it would be best to watch it on the small screen with such children, or at the very least accompany the film with a discussion about imagination and fiction.
Overall, it's a wonderful movie for kids of all ages. Enjoy!