Trying to decide between catching the latest flick at a Regal multiplex or the Music Box Theatre is like debating whether to see the Cubs on TV or at Wrigley Field; you’re watching the same thing but having a totally different experience. There’s no moviegoing destination in town that comes close to the Music Box’s main room, built in 1929 to seat 700 people, its ceiling a dusky blue night sky with bulb-lit stars, surrounded by plaster columns, hanging jewel-like lamps, ogee arches, and faux-marble busts. To absorb classic Hollywood splendor at its least diluted, visit the Music Box during one of its annual special events, typically devoted to repertory screenings. If you have to mark one occasion for your calendar, make it the Christmas Sing-A-Long, where even the most hardened Grinch will succumb to the toasty burbles of live organ accompaniment and a packed house collectively hissing whenever Mr. Potter appears onscreen in It’s a Wonderful Life. 3733 N. Southport Ave., Lake View