Imagine "Superman" with a Clark Kent more charismatic than the Man of Steel, and you’ll understand how "Spider-Man" goes wrong. Tobey Maguire is pitch-perfect as the socially retarded Peter Parker, but when he becomes Spider-Man, the film turns to action sequences that zip along like perfunctory cartoons. Not even during Spidey’s first experimental outings do we fell that flesh and blood are contending with gravity. Spidey soars too quickly through the skies of Manhattan; he’s as convincing as Mighty Moust