The Once Respectable:  Henry Winkler of Happy Days

At His Best:  Anti-social, cool, known for starting jukeboxes with his bare fists, making pointed use of a switchblade comb, dating twins or riding a motorcycled daringly over trash cans.

At His Worst: Well...come on.  Just look at it.  Look at it and remember that by the end, Fonzie was a teacher with an adopted son and a passion for civic involvement.