As a rabid James bond fanatic since I was very young, I'm partial to Sir Sean Connery. The original. The best... there is no substitute.
George Lazenby was a diamong in the rough; had he not followed bad advice and p*ssed off Cubby Broccoli and Harry Saltzman, he'd be more than just a one-Bond wonder.
Roger Moore wasn't too bad, but he was too English and too refined to be James Bond, in my opinion.
Timothy Dalton played the part very close to the literary James Bond of Ian Fleming. Unfortunately, the world wasn't quite ready for a totally ruthless 007.
Pierce Brosnan runs a close second on my favorite Bond list; he portrays the part with a little bit of Connery panache and Dalton ruthlessness.
Errr... just a drink. A Martini, shaken, not stirred.