I actually just recently finished going through the "Bond 50" Blu-Ray set. I've had it for a while now, but just never got the chance to actually sit down and watch all of them.
So with all of the Bond movies, including the non-canon ones, in recent memory... I think my order for the official Bonds would be...
Connery > Brosnan > Dalton > Craig > Moore > Lazenby
I admit likely bias toward Connery and Brosnan. I grew up watching these movies with my dad, and Connery is his favorite. We watched "Goldfinger" a lot when I was little. So when someone says "James Bond," it's the image of Sean Connery that comes immediately to mind for me.
My bias toward Brosnan is because "Goldeneye" was the first Bond movie I could see in theaters (born in '88), and I played the hell out of all the Bond video games that used his likeness. I do think he's a legitimately great actor for the role, though. It just bites that he only really has one great movie out of the bunch. He was a great actor doing his best with a bunch of shitty screenplays.
Dalton and Craig were close, and which I like better is probably going to depend on the mood I'm in. They both play darker Bonds... but I think Dalton did a better job. Craig has gone on record as not wanting to make Bond movies anymore, and it kinda shows. He always seems somehow... out of place. I'd be curious to know to what extent he's half-assing it and phoning his performance in for a paycheck. I also don't particularly care for Craig's movies after "Casino Royale." I know it's the popular thing to hate on "Quantum of Solace," but I actually thought "Skyfall" and "Spectre" were almost equally as disappointing. I can see myself wanting to watch Dalton's movies again, but not so much with Craig.
I've never liked Roger Moore, nor his movies. He plays the part a lot more campy, like a parody. He lacks the charisma of the other actors, and he can't seem to fire a gun without flinching. His movies have the cringeworthy "J.W. Pepper" cameos and fucking slide whistle sound effects. SLIDE WHISTLE in a James Bond movie. Bah!
George Lazenby I don't really have an opinion of. He was a rookie to acting and was in way over his head. Maybe if he'd stuck with the role longer he would have fit in given time (assuming they stopped giving him shitty fourth-wall breaking lines), but it just wasn't meant to be. From the stuff I've seen and read about his experience filming OHMSS, it kinda fucked up his whole life for a while.