THE BIG EASY - That's a nickname for New Orleans, where a policeman falls in love with an assistant DA who's sniffing out corruption in his department. Dennis Quaid is capable but not memorable as the cop. Ellen Barkin shows amazing strength and versatility, though, as the snoopy outsider. Directed by offbeat filmmaker Jim McBride, who gives the action a lot of energy but falls back too often on the usual sex-and-violence formulas. (Rated R) DIRTY DANCING - Jennifer Grey gives a sassy and captivating performance as a teen-age girl coming of age during a Catskills vacation with her parents. Details of the 1963 period are weakly handled, though, and the ending is as false as it is sentimental. Directed by Emile Ardolino. (Rated PG-13) HAMBURGER HILL - The latest Vietnam war drama portrays the young men who fought the conflict's most notoriously pointless and difficult battle. It's as violent as ``Platoon,'' which it resembles in its anti-``Rambo'' depiction of combat's ultimate horror and futility. What makes it different from other recent Vietnam-related films is its revealing account of racial divisions among American soldiers. Philip Glass composed the occasional music. The language is as foul and ferocious as the fighting, which seems to be a rule of the new Vietnam-movie genre. John Irvin directed. (Rated R) INSIDE OUT - Effectively weird drama about an agoraphobic man who hasn't left his apartment in years, and whose life is shriveling up before his eyes. Not for every taste, but a hopeful finale eases the story's chill. Elliott Gould gives his best performance in years, and maybe ever. All told, a daring and imaginative, though murky film. Robert Taicher directed. (Rated R) THE MONSTER SQUAD - Youngsters fight an invasion of Hollywood-style monsters. The tongue-in-cheek plot takes its cue from ancient pictures like ``House of Dracula'' and ``Frankenstein Meets the Wolf Man,'' which shoehorned whole gaggles of big-name monsters into their wildly contrived story lines. The makers of this opus clearly like old horror flicks and revive some of the old traditions: Frankenstein's monster is a softy at heart, for instance. But the plot is lumpy; the characters are hackneyed; and the action and special effects are often way too yucky for younger children. Fred Dekker was the director. (Rated PG-13) RENDEZ-VOUS - An aspiring actress gets involved with a real estate clerk and his roommate, a deeply neurotic actor. The frequently sordid action is long on mood, short on meaning. Andr'e T'echin'e directed the French production. (Not rated) WHERE THE HEART ROAMS - Entertaining documentary about writers and fans of romance novels, filmed during a cross-country trip to a convention in New York. Like the people he observes and interviews, director George Paul Csicsery takes the subject of romances a lot more seriously than it deserves. But he serves up a screenful of colorful personality portraits and gives a vivid sense of what the romance genre is all about for its most dedicated followers. (Not rated) RATINGS: Films with ratings other than G may contain varying degrees of vulgar language, nudity, sex, and violence.