From reading the previous reviews it is apparent that this novel polarises opinions like few others, i.e. you'll either love it or hate it. People who hate it find the language archaic, "eighteenth century nautical terms scattered like confetti", the characters wooden and hard to sympathise with, and struggle to engage with the novelist. Many readers, perhaps enticed by the Russell Crowe film, will find themselves buying this book and then struggling to get beyond the first chapter. It is not easy reading, not like Sharpe, or Hornblower that you can race through, especially at the outset. However, if you like a book with a bit of substance behind it, are prepared to do a little bit of work to understand what is going on, and will give the characters room to breathe, you may just find yourself rewarded beyond expectations as a treasurehouse opens up before you.
This is the first of a series of twenty novels and you really do need to read them in sequence, (1. Master and Commander, 2. Post Captain, 3. HMS Surprise etc.),as the author tends to tell you something once and then expects you to remember it. If you start with The Far Side of the World, number ten, because of the film, you will be hopelessly adrift; nothing the characters do or say will make any sense, and the plot is very different from the film so you will not recognise what you are reading.
Start with this one then, book one and don't just skim it for the adventure story. Climb the rigging with the lubberly Dr Stephen Maturin and listen as he has explained to him the masts, yards and sails of the Sophie. After only a few pages you know the difference between the foremast and the mizzen, the stays, tops and ratlines. You will benefit from getting some maps; Minorca and the Spanish coast east of Gibraltar (look them up as soon as the place names come out of the text). You want to get a feel for the shape of the coast, harbours and ports. Don't spend any money, just five minutes with the Google map facility and print them off, nicely magnified so you get all the capes and points. Now you can feel the tension as the Sophie ducks under the enemy guns, steals a prize and races for safety with a half dozen frigates in hot pursuit; all the naval engagements make a whole lot more sense; you might even mark the positions of the vessels and follow their movements; Patrick O'Brian gives you enough description to clearly visualise every detail and this is where he scores most of his points and wins his lifelong devotees. The author had vast resources of knowledge about naval engagements of the period and most of the action is painstakingly recreated from real events, as reported by those who took part in them. This is far more than historical fiction, it is the bringing back to vivid life of a period of our relatively recent history.
Next if you find the story intriguing but the nautical terms frustrating (you are not alone in this), you might consider purchasing a reference book: The World of Jack Aubrey by David Miller (I paid £5.99), a shortish, hard-backed book for the twenty-first century reader, full of diagrams and explanations and with a glossary of technical terms. The mysteries of the stunsail, the use of the log, the bells of the watch and the use of the glass will all become clear, along with good descriptions of the various vessels that feature, from lateens to bum-boats, sloops and brigs, the points of the compass and the different fighting styles of the British and French men o' war (British preferred solid shot aimed at the hull that sent explosions of splinters through the enemy crew, wheras the French preferred chain and grape shot to disable and capture.
A further book is a worthwhile purchase, Admiral W.H. Smyth's The Sailor's Word-Book (Conway £9.99). This fat period tome comprises over 14,000 nautical and naval terms, every technical word used by Patrick O'Brian is in there, described in crisp clarity, the Admiral spent the seven years of his retirement from 1858 - 1865 working on this mine of information and the Aubrey/Maturin enthusiast will have this reference close by at all times.
To bring the experience fully to life I would also recommend a day out to the Portsmouth historic harbour; a couple of hours inhaling the air aboard the H.M.S. Victory touching the cables and absorbing the perspectives will be well spent.
If you find yourself shouting, "Vast that anchor", to your wife in the Sainsbury's car park, and your kids buy you a parrot for Christmas then it's possible that you might be allowing your enthusiasm to carry you a little too far, but until then, enjoy the journey.