I did a fanedit (never released) that used Spider-Man 2 as the foundation, with part 1 used as flashbacks to flesh out Harry's reason for hating Spider-Man, and his relationship to Norman Osborn. Parts of Spider-Man 3 were used to finish the story of Peter/Harry without having to watch the rest of part 3 (Venom/Sandman/Gwen stuff).
As for JUST Spider-Man? Maybe just toning down the campiness, but not losing the story? Not sure, it's something I'd have to think about.