I had interpreted the OP to mean best lines by Bond, not necessarily just by anyone in a Bond film. But with that broadened criteria, I submit, from The World is not Enough, this line by Zukovsky, after Bond ambushes him from behind a door, at gunpoint:
I’ve always liked Dalton’s comeback at the top of the IMDB’s quotes page for that film:
Kara Milovy: You were fantastic. We’re free!
James Bond: Kara, we’re inside a Russian airbase in the middle of Afghanistan.
'course, it’s dated now. Who remembers Afghanistan, and the Mujahideen? Ah, the mid-80s. Back when the Libyans were the baddies and people were worried about nuclear reactors. I remember blowing up Libyan SAM sites in F-15 Strike Eagle II, simpler times.
But, also this quip, from From Russia with Love:
[Moneypenny, M, and other officials are listening to Bond’s taped interview of Tatiana Romanova]
Tatiana: The mechanism is… Oh James, James… Will you make love to me all the time in England?
James Bond: Day and night. Go on about the mechanism.
It’s the delivery that does it; he says “day and night” as if she was offering him a cupcake. Bear in mind that Tatiana looked like this:
The lovely Daniela Bianchi there, one of a seemingly endless string of extraordinarily attractive women scattered throughout the Sean Connery Bond films. They all seemed to be get married to extremely rich people before retiring from the silver screen.
See, as a kid I thought the Connery Bonds were boring, because they didn’t have spaceships or Sheriff J W Pepper, but after buying a boxed set of the Connery Bonds a while back I’ve come to the conclusion that I was a stupid, stupid child. They’re entertaining, like a three-course meal, and I can’t imagine the impact they had on audiences in Britain in the early 1960s.
Dr. Christmas Jones: The world’s greatest terrorist running around with six kilos of weapons-grade plutonium can’t be good. I gotta get it back, or someone’s gonna have my ass.
Amusingly, now you mention it, Cleese has to show Bond that bloody car. I think we’ll have to agree to differ on DAD though. The shoe-horning in of Madonna is particularly egregious, as is the over-emphasis on in-jokes (just because it was the 20th of the series), all of which happens before Cleese comes on. As you note from there on it is pretty awful - any film that requires the whole franchise to be rebooted is not covering itself in glory. Shame really, as it wasted a pretty good set up (Bond spends 14 months being tortured after capture and has his licence revoked under the assumption that he cracked).
“There were a lot of things he could say. “Son of a bitch!” would have been a good one. Or he could say, “Welcome to civilization!” He could have said, “Laugh this one off!” He might have said, “Fetch!” But he didn’t, because if he had said any of those things then he’d have known that what he had just done was murder.”
In Never Say Never Again (I think, correct me if I’m wrong), Bond’s in a health spa, and a nurse is standing about six feet away from Bond, and tells him to fill a cup (for a urine sample).