Before Andrew Lloyd Webber's tourist trap of a megamusical (presently being transformed for the movies by director Joel Schumacher) and before a slew of other screen versions (with actors as various as Casablanca's Claude Rains and A Nightmare on Elm Street's Robert Englund as the lead ghoul), there was the silent classic starring Lon Chaney. Phantom's enchantment begins when Christine, an opera ingenue, ventures through her dressing room's looking glass and into the catacombs of a masked madman. Though it's rightly regarded as the first great horror film, it also seems possible that what makes it great -- its tender dreaminess, the sympathy Chaney swiftly earns -- disqualifies it as ''horror.'' The movie's really rather sweet. The set includes both the 1925 original and 1929's suitably operatic restoration. I'd be tempted to label the handful of extras (a slickly authoritative audio commentary, a stills gallery, an interview with the cinematographer) For Geeks Only, if the movie, in its combination of gothic grandeur and simple pathos, didn't threaten to make geeks of us all.