Tall and gangly, with an infectious energy that added spark to all of his work, actor Matthew Lillard had his breakthrough role as the creepy Stuart in "Scream" (1996). While his film debut came with a job as an extra in the forgettable 1991 sequel "Ghoulies III: Ghoulies Go to College", more significant was his first featured film acting role, as the teenaged son of the title maniac in John Waters' "Serial Mom" (1994). Frequently cast as weirdoes, undoubtedly due to his frantic physical edginess, Lillard previously portrayed off-balanced computer genius Cereal Killer in "Hackers" (1995). That