Who's the better John Travolta, Jimmy Fallon or John Travolta? You probably already know the answer, but Fallon held a John Travolt-Off challenge on The Tonight Show Thursday to decide once and for all. When pressed, the random Travolta generator pulled one of the actor's many famous movie roles for them to replicate in front of the audience. Fallon did his best impressions of Tony Manero in Saturday Night Fever and Vincent Vega in Pulp Fiction, but then in came Travolta himself who reenacted Danny Zuko in Grease and Castor Troy in Face/Off. Challenge owned. Together, they then danced it out in the voice of Vinnie Barbarino in Welcome Back, Kotter. Fallon kept saying, “How do you do that?!” Well,