Screen Tests:
From the main menu go to the "Beyond the movie" menu.

Then stand on the option "The Terror Gauge" and press your Right button on your remote one time and then "down" one time and a picture of some thunder and lightning will appear on the TV (I think it's a TV…)

Then press "Ok" and you'll see several Screen Tests from the Actors.

Bonus Clip:
When you start the movie, right before the company logo disappears, hit Previous Chapter, there's a hidden clip of some of the people in charge of the movie.