I'd call Tolkien works children stories. It's best to read them around 10-12, later they are well... too naive and childish to enjoy them fully.
Oh, there is also good recommendation for all fantasy lovers - with success of The Witcher it seems they translated some books the game was based on. Check amazon for Andrzej Sapkowski, I see at least "The Last Wish" there, the first tome of the saga. He is the best Polish fantasy write, so if translation is good, it's really worth it. Mature fantasy
