Even though Chamber of Secrets is one of my favourites of the movies, the book is probably my least favourite of the books. This contrast is interesting, because the story has one of the most interesting premises of the series, in my opinion, with the mystery of who's behind the petrifying,and Harry really questioning who he is and if he fits in with Gryffindor and Hogwarts. His showdown with the Basilisk is also a great moment in the series, and the Polyjuice Potion part is really interesting, but the story also feels kind of like it drags at times, and there are parts that just don't really hold my attention (including the Deathday Party). I feel like the movie really did a great job at keeping the best, most interesting and relevant parts, and that's why I really enjoy the movie version compared to the book
(The book is still not bad at all, in my view, and I do have quite a bit of nostalgia for it. For me it's just the weakest book in a series of superb books)