From Disc Two's main menu, go to "Cast and Crew". In this section, you'll not only find entries for the film's cast and crew, but you'll also find mock "biographies" for the film's characters. To access these, highlight any actor's name, press down to highlight his/her character's name, and hit enter.
As with many New Line titles, the DVD credits for this disc can be accessed by clicking on the New Line logo on the right side of the main menu. (This only works for Disc Two.)
Reviews: DVD Talk also has a review of
Boogie Nights: Special Edition by Aaron Beierle.