D.H. Lawrence Novel Is a Switch for Ken Russell. FILM: REVIEW

AT a time when many filmmakers like to play it safe, Ken Russell likes to do the opposite. Early in his career, he showed a knack for popular, mainstream pictures like ``Billion Dollar Brain'' and ``Women in Love,'' which earned Glenda Jackson an Oscar as 1970's best actress. But such conventional projects were too tame for Mr. Russell. Soon he was flabbergasting audiences with kinky scenes from ``The Devils'' and turning his love for music into streams of bizarre images in ``Tommy'' and ``Mahler'' and ``Lisztomania.''

In recent years, Russell has poked his toe into the mainstream once or twice - his ``Altered States'' was an almost conventional horror movie - but movies like ``Salome's Last Dance'' and ``Gothic'' were closer to hallucinations than entertainments.

His last picture, ``The Lair of the White Worm,'' told a recognizable story, but its style was right out of nightmareland.

So it's quite a surprise to find Russell back in the world of conventional moviemaking (in style, if not always in content) this year. With one notable exception, ``The Rainbow'' is almost old-fashioned - in its story, the way it's made, and even its characters, a number of whom are from the same family that ``Women in Love,'' adapted from the D.H. Lawrence novel, focused on almost 20 years ago. However, that exception - Russell's graphic fascination with sexual passions - will put ``The Rainbow'' firmly off-limits for many filmgoers.

The main character of the film is Ursula Brangwen, a young woman coming of age in rural England at the turn of the century. Like many of Lawrence's characters, she has too much energy and imagination to accept a time-honored way of life that her family and neighbors never question. She becomes a teacher and tries to fit in with the British educational system, but it confines her so much she feels tortured by it.

More controversially, she also has a couple of stormy love affairs - one of them with another woman - in her search for physical and emotional freedom. Although she never quite finds this freedom, the movie ends on a note of hope.

Russell has never been known for his good taste, and ``The Rainbow'' finds him true to form at times, especially when Ursula gets sexually involved with a female schoolteacher, in scenes explicit enough to deserve the movie's R rating and then some.

Other aspects of the film are uncharacteristically traditional, however, including the bright-eyed performance of Sammi Davis as Ursula - she's a perfect Ken Russell actress, with her bold features and extroverted manner - and the sturdy acting of Glenda Jackson as her mother.

Unlike the sprawling and uneven Lawrence novel, Russell's movie is less a family saga than the story of one young woman, set against an increasingly modern and unpleasant English countryside that Lawrence and Russell criticize (much like Dickens before them) for losing its humanity in the name of progress. Despite its limitations and its excesses, ``The Rainbow'' does a convincing job of capturing England as it moves into a challenging, and in some ways frightening, new century.