Who's asking: Steven Dean, Mechanicsville, VA
The answer to this question would depend on the circumstances. If Jason Bourne and James Bond met by chance in a dark alley, Jason Bourne would win: he's more cunning and more ruthless. If they met under work-related circumstances, James Bond would win, because he has Q and all those cool gadgets.
In related questions, Superman would beat Batman, Donald Duck would kick Mickey's butt, and Dirty Harry would blow Rambo away.
Please leave your own fantasy grudge matches, with their projected winners, in the comments section.