From the main menu, with any of the three options highlighted, press down to highlight the text "Hear Tappy's Amazing Life Story!" on the far bottom of the screen. Hit enter to watch a five-minute portion of the Tappy Tibbons infomercial featured prominently in the film.
From the "Chapter Index", highlight "Chapters 21-24" and press up twice. Hit enter to watch another 2.5-minute chunk of the Tappy Tibbons infomercial, which includes the "third thing that will change your life" that was never revealed in the film.