I'll actually say Lou Albano. I've never seen the Super Show, but he does do the Do The Mario dance at the end of each show, and how cool is it that a wrestler plays as a game character? Okay, not so cool anymore, but as a kid that would have rocked. If I had any clue who Lou Albano was, that is.
...which means my vote is that I thought Bob Hoskins did worse.
I agree that John Leguizamo was pretty bad as a choice for Luigi. No moustache, didn't sound a thing like Luigi. And Luigi got the girl. For Luigi fanboys, that's a dream come true, but for me who didn't see the appeal of Luigi back then, I was wondering "Hey! Why isn't Mario the winner?"
Amuses me to no end that when Nintendo Power was describing the movie, it admitted to all its fans that the movie would be very different from the games. Goombas are not as we know them, Yoshi's completely different, I think they also mentioned Daisy. I know that had I read that article, I would have immediately lost interest in the movie. Or I would have expected it and thus have gone in with a more proper mindset, having lowered expectations.