Bonus Documentary
On disc four, select [Production] from the [Main Menu]. On the [Production] menu press [Up] to highlight an icon in the top right. Selecting it will play a short documentary.
Bonus Featurette
On disc eight, hightlight [Post Production] and press [Enter]. Highlight [More] and press [Enter]. Highlight [Back] and press [Down] to highlight the warrior icon at the top of the screen. Press [Enter] to see the hidden featurette "Be Careful What You Wish For...".
DVD Production Credits
On disc two, highlight [Navigation Options] and press [Enter]. Then enter the numbers [52579] (the U.S. theatrical release date for Alien, May 25, '79) to get the DVD production credits.
On disc four, highlight [Navigation Options] and press [Enter]. Then enter the numbers [71886] (the U.S. theatrical release date for Aliens, July 18, '86) to get the DVD production credits.
On disc six, highlight [Navigation Options] and press [Enter]. Then enter the numbers [52292] (the U.S. theatrical release date for Alien 3, May 22, '92) to get the DVD production credits.
On disc eight, highlight [Navigation Options] and press [Enter]. Then enter the numbers [112697] (the U.S. theatrical release date for Alien Resurrection, Novenber 26, '97) to get the DVD production credits.