I know almost everyone in America has read or watched The Lord of The Rings, but the predecessor book to that trilogy (The Hobbit) is a great read for young kids. Either reading it themselves or you reading it to them this book is much more lighthearted and adventure filled than the Rings books.
It also is much funnier and more appropriate to young readers. I am reading it again (we have gone through three copies now) and am going to read it to the kids this summer. A great book for boys or girls.