A CRITIC AT THE TOP OF HIS VOICE: Review

His digressions notwithstanding, Mr. [HARLAN ELLISON] does get around to critiquing movies, most of which he finds lamentable for their dishonesty and inaccuracy (''Rambo,'' ''Enemy Mine''), appalling derivativeness (''Starman,'' ''Back to the Future'') and inept plotting and characterization (most of the Stephen King adaptations). The culprits are the Steven Spielberg-George Lucas flock of television-bred film makers who target young audiences ''for whom nostalgia is remembering breakfast.'' When he finds a director he admires (William Friedkin, Terry Gilliam, Ridley Scott), he can hardly believe his good fortune. In contrast to the detached, impersonal tone of the average film critic, Mr. Ellison pronounces almost exclusively at the top of his voice. His brickbats are Bunyanesque (''Buckaroo Banzai'' is a ''village idiot of a movie''), his bouquets as big as parade floats (''Brazil'' is ''brilliant beyond the meaning of the word''). His style routinely mixes a standard critical idiom with esoteric vocabulary, slang, a liberal use of obscenities and many homemade coinages.