I've been to a few retreats now and I keep hearing the advice of 'start your novel with action'. While I bow to the experts who've been in the business far longer than myself and have sold thousands of books, I don’t necessarily agree with that. Perhaps it’s a genre specific thing of genres I don't write! The statement is too vague and easy to misunderstand. Too many people take it literally and feel like they have to start their book with explosions, murder, a chase, a fight, something huge and dramatic. But I don't think that's really what the advice means.
When you think of action try not to think of it as a Hollywood thing, think instead in a literary sense. Better yet, replace the word action with tension. War And Peace didn't start with action but it definitely started with tension.
So what does that mean? How should you start your book? Somewhere near the beginning of your book should be the catalyst, the thing that sets everything in motion and brings your protagonist to the inevitable end of the book. You can start with the catalyst. I often do myself. But if there's something else, something that will build tension and add to the plot then you can start with that. Just remember, the key is to catch the reader's interest with some kind of tension or a desire to know more.
Check out this great post on The Biggest Bad Advice About Story Openings by Jane Friedman of Writer's Digest: http://blog.writersdigest.com/norules/2010/03/11/TheBiggestBadAdviceAboutStoryOpenings.aspx