The London Times lists some of the worst James Bond movie moments. I disagree with a lot of their choices, especially when there are so many truly awful moments to choose from.
For me, the worst moments were in "Moonraker" (Jaws flapping his arms, trying to fly as he fell from an airplane; Bond riding a horse to the theme from "The Magnificent Seven"), "A View to a Kill" (Bond skiing across an ice-lake to a Beach Boys song; getting into bed with Grace Jones and looking like a dirty old man), "On Her Majesty's Secret Service" (007's arch-nemesis Blofeld doesn't recognize Bond because he's wearing a kilt!), "Diamonds Are Forever" (Bond tooling around the desert in a moon buggy), and "Die Another Day" (the invisible car and a ridiculous CGI Bond surfing a tidal wave).
(Thanks to Bill Crider for the link)