The parties within its walls were glitzy, the arguments were epic and the scandals provided perfect gossip fuel. If only houses could talk: This one, however, is a battered shadow of its proud Regency past, its interior walls torn apart, trucks parked on its tennis court. Its only occasional visitor is David Zaslav, newly minted king of Hollywood, who comes to commune with its ghosts and summon up plans for its glistening future.