A blonde. blue-eyed character player of American films and TV, Diana Scarwid had a natural quality and keen instinct for underplaying roles to exemplary fruition. She won wide praise and an Oscar nomination for Best Supporting Actress for her work as Louise, the waitress who is the object of John Savage's affections, in "Inside Moves" (1980). But, be it because of camp or a more widespread release, Scarwid probably is better remembered for her portrayal of Christina Crawford, daughter of Joan ("No Wire Hangers!") Crawford in the dubious "Mommie Dearest" (1981).