Hundreds of riders had to be rescued from a J train near the Sutphin Boulevard station when a track fire stranded the train. A mechanical failure reportedly sparked two small fires, forcing many passengers to climb out of the car and walk along the tracks to the above ground 121st Street station before firefighters arrived. So which is worse, putting yourself in danger walking along the tracks, or waiting hours in a subway on a humid day for firefighters to pry you out?