Enter the "Extra Features" screen and press Down to highlight the acid pool at the bottom of the screen. Press Enter to view data compiled by Kane regarding the alien's life-cycle.
Credits
Highlight the "Extra Features" option at the main menu and press Left to highlight the left window. Press Enter to view a credits screen featuring the disc's developers.
Nostromo data
Highlight the "Scene Selections" option at the main menu and press Right to highlight the right window. Press Enter to view data about the Nostromo and its crew.