When I was little, I really liked Little Golden Books, and then books from the Scholastic Book Club. Grew out of them rather quickly, though, and never had an interest in "tween" books like Nancy Drew, Little House, etc. I proceeded from children's books directly to adult-level books.
I also liked some of the "antique" school books passed down from my aunt and mother, and a couple of really old ones my grandmother had had.