G'day mate!
I think I did see the movie first. I've happly seen it a number of times and recently purchased the Blu-ray disc. And I've read the hardcopy book, too. I think Russell Crowe is a perfect Jack Aubrey, so when I read/listen to the book I enjoy being able to visualize Aubrey. And I think Paul Bettany was a fine Stephen Maturin, too.
One thing to keep in mind is that the movie is based on 2 novels: Master and Commander and Far Side of the World. I haven't read the latter, but I think it's clear that the movie is based mostly on Far Side of the World. So not much from M & C will be spoiled if you read it.
Although, like the movie, M & C is a great yarn, it is a historical novel. That is, O'Brian obviously did an immense amount of research about the Napoleonic era, and about the British Navy, naval warfare, and the operation of fighting ships. And the book can get pretty detailed about the nuts and bolts of operating a naval vessel. Don't be frustrated if you don't understand much of it (neither does Maturin). The take away is that seamen had to have extensive knowledge to perform their duties.
M & C also excels at getting inside the characters, particularly through Maturin's thoughtful observations of Jack as well as others.
O'Brian skillfully blends all of this together. I think M & C is a substantial work of fiction as well as being an enjoyable adventure story. If you choose the audiobook, Patrick Tull does a great job of narration. You won't go wrong either way.
Les (Eutychus)
