Asking the clerk at your video store for a lighthearted whodunit might not be the best way to find a Nick and Nora mystery. And flipping through most of the paperback guides probably won't get you much further unless you already know the movie's title. So to help you scratch that video-rental itch, two new reference CD-ROMs, COREL ALL-MOVIE GUIDE (Corel Corp., for PC and Mac) and BLOCKBUSTER VIDEO GUIDE TO MOVIES & VIDEOS (Creative Multi media, for PC), debut, and a third, VIDEOHOUND MULTIMEDIA (Visible Ink, for PC), reappears in an updated edition. Each bills itself as a nostrum for renters, bringing together the worlds of cybersurfers and couch potatoes with cross-referenced reviews, clips, photos, and interviews.
With encyclopedic breadth, Corel includes 90,000 reviews that attempt to quantify nearly every aspect of a movie by assigning numerical rankings to such intangibles as historical significance. Unfortunately, it's also peppered with minor errors. Blockbuster avoids factual missteps but then, it doesn't offer many facts. It also adheres to its chain-store namesake's family-values philosophy by not reviewing NC-17 titles among its 21,000 listings, though it reviews unrated video versions of such movies as Betty Blue and Crimes of Passion. More broad-minded viewers might find VideoHound Multimedia more digestible, with its B-movie production values and such spunky warnings as ''big-budget stinker.'' Culled from the book VideoHound's Golden Movie Retriever, it covers only titles available on video; still, it boasts 60,000 listings.
None of the three discs offer big-name critics like those found on Microsoft's Cinemania '95 (such as Leonard Maltin and Pauline Kael), but each usually manages to turn in similarly levelheaded judg ments. All, for example, give Lawrence Kasdan's 1983 The Big Chill a thumbs-up. But Blockbuster's review reads like a local TV listing, and its related bios lean more toward pedantry than personality (it calls Kasdan's Grand Canyon ''an unconscious record of Hollywood's pious liberalism''). VideoHound's write-up has more panache and includes information about closed captioning. Corel's listing adds domestic grosses and exhaustive credits, right down to set decorator, which might explain the $70 price tag.
For all its comprehensiveness, Corel includes some hilarious flubs. The time-period heading for The Big Chill is given as ''Middle Ages'' (er, it's about middle-agers); elsewhere the disc refers to Kevin Costner in Body Double (make that The Bodyguard). In November, the company plans to release a corrected version, free to registered owners.