Let's say hypothetically, a Spider-Man movie was made in the 1980s and he didn't come down with Parkinson's, I could honestly see Michael J. Fox as a decent Peter Parker. He has both that everyman appeal needed for the role and based on his sitcom work, could convincingly transfer Spidey's trademark wit and sarcastic streak. My main concern, would of naturally been, his height. Spidey is like 5'10 in the comics, whereas Michael J. Fox is about 5'5.