I was going to say the beginning of For Your Eyes Only.That is my favorite opening sequence of all the Bond films with the helicopter but if I HAD to choose,it would be the scene in Live And Let Die when Bond is tied up in a rope with Solitaire being lowered into the water with the sharks.The theme song music of Live and Let Die and the shots of him using the watch to cut through the rope just make that such a fun scene to watch over and over again.Its very close between those two.I love them both.
Difficult to say. I might just go with this.
I also have a unique fondness for first scenes with Roger Moore as Bond in LALD at his home and after he is captured inside the restaurant in Harlem.