Boston Celtics vs NY Rangers? They aren't even the same sport. The only Boston/NY rivalry worth noting is Red Sox/Yankees.
As far as the world's greatest football rivalry, I think my allegiance is pretty obvious. Yeah, was anyone else thinking this when they popped in here? I thought that video was a bit funny, especially the part at the beginning where they had to subtitle that poor moron.
The Old Firm matches are pretty brutal. It's pretty rare that they can go down without several stabbings.