Film version of books are always a risky proposition unless you can get a director who absolutely loved the original work. The only ones that seemed to have worked that I can think of are the Bourne series, the Lord of the Rings series, The Colour Purple (as far as I can remember, its been a while since I read it) and if you really want to stretch it 300 and The Watchmen (yes I know they were graphic novels but the principle still stands).