Tough one, umm:
1. Fangio
2. Senna
3. Clark / Stewart
Almost in : Prost (wet weather?), Moss (unfortunate place in time), Brabham(3 WDC including one in his own car - do that Shumi
)
1. TGF
2. Montoya
3. Ralf
Almost in : Alesi, Jacques (when he wants to)