If a child can watch <i>Barney</i>, can't that same child also enjoy watching Charlie Chaplin or the Marx Brothers? And as they get older, wouldn't they grow to like screwball comedies (<i>His Girl Friday</i>), women's weepies (<i>Imitation of Life</i>), and westerns (<i>The Searchers</i>)? The answer is that they'll follow because they'll have learned that “old” does not necessarily mean “next channel, please.”<br><br>Here is an impassioned and eminently readable guide that introduces the delights of the golden age of movies. Ty Burr has come up with a winning prescription for children brought up on Hollywood junk food. <br><br><b>FOR THE LITTLE ONES (Ages 3</b>—<b>6): </b>Fast-paced movies that are simple without being unsophisticated, plainspoken without being dumbed down. <i>Singin' in the Rain</i> and <i>Bringing Up Baby</i> are perfect.<br><br><b>FOR THE ONES IN BETWEEN (Ages 7</b>—<b>12): </b>“Killer stories,” placing easily grasped characters in situations that start simply and then throw curveballs. <i>The African Queen </i>and <i>Some Like It Hot</i> do the job well.<br><br><b>FOR THE OLDER ONES (Ages 13+):</b> Burr recommends relating old movies to teens' contemporary favorites: without Hitchcock, there could be no <i>The Texas Chainsaw Massacre,</i> without Brando, no Johnny Depp.