Color me charmed. I started the Narnia Chronicles with the first novel written, The Lion, the Witch and the Wardrobe and then went in the numbered order on the books, leaving this book, chronologically first, for last. I'm glad I did. I think you enjoy this tale about the creation of Narnia a lot more if you don't read this novel first. I think you should at least wait until you've read The Lion, the Witch, and the Wardrobe or you won't appreciate as much details from the beginnings of the White Witch to the origin of the lamp post.
I actually didn't adore The Lion, the Witch and the Wardrobe because I found the Christian Allegory too blatant, but that aspect didn't bother me at all in this book for some reason. Less than in any of the other books, even though if The Lion, the Witch and the Wardrobe is the Gospels and The Last Battle Revelations, then this certainly is Genesis. But it's so imaginative and glorious--Aslan singing Narnia into being:
"Narnia, Narnia, Narnia, awake. Love. Think. Speak. Be walking trees. Be talking beasts. Be divine waters."
I think there's a bit of political allegory here too--the "Deplorable Word" (and maybe even the figure of the Magician) referring to our nuclear age and the so-called "sin of the scientist."
There were aspects of the Chronicles that jarred and disturbed me. Although I don't agree with those that accuse Lewis of racism and sexism, the books were written in the 50s and there are wince-worthy moments. Like for instance in The Silver Chair with its slam at co-ed schools or The Last Battle with its description of the Calormenes. I can't recall any moments like that in this novel however.
In fact the way Digory and Polly were depicted reminded me of how gender-balanced Lewis is in these tales--with the girls just as brave, smart and important to the adventure as the boys. I also thought in a lot of ways this was the most moving of the Narnia tales. Digory has something personally at stake he cares about in our world--his mother--and that made me care more about him than I did most of Lewis' children protagonists.
I also hated how The Last Battle ended, so I'm rather glad I left this book for last--definitely leaving Narnia on a high note.