My favorite completely stupid Spider-Man fight is the one where he and Namor have a throw-down because Namor thinks he kidnapped Sue. Because JOHNNY told him that Spider-Man kidnapped Sue. Very reliable witness there, Namor! Actually, Spidey was taking Susan out on a date and Johnny was all annoyed, and so ... yeah.
Incidentally, Spidey didn't win; he just managed not to get killed before Sue figured out what happened and got Namor to lay off.