As expected, Harry Potter and the Half-Blood Prince made its pre-Christmas debut on DVD last week and instantly bounded to the top of the Nielsen EDI VideoScan sales chart. (Early in the week it was reported that the movie set a first-day sales record in the U.K., where 840,000 copies were sold in 24 hours.) Somewhat surprisingly, the film, which earned $302 million in theaters, placed second on Home Media magazine's rental chart, beaten out by the Johnny Depp gangster movie Public Enemies , which earned $97 million in theaters. ( Enemies placed second on the sales chart.) Other top sellers 3. Julie & Julia (New); 4. Star Trek (fourth week); 5. Night at the Museum Battle of the Smithsonian (fifth week).