Like most legends that can talk, Dame Ninette de Valois is a treat.

"I'm not one of your old ladies who does exercises every day," she said recently at a Manhattan restaurant as she tucked a large linen napkin firmly under her chin. "I hated them when I was dancing, and I stopped doing them when I stopped dancing. I mean, what's the point?"

Dame Ninette exudes the ruthless honesty afforded someone who is 81 years old. But, clearly this is not new to her. Like many of the earth-shakers of this century, she has lived independently, directed autocratically and expected as much from others as she has from herself.

"I'm not a good person on committees" she conceded. "I've spent my life on them, and you go around in a circle and end up exactly where you started. I've got a bad temper and little patience."

Dame Ninette attended to her eggs Florentine and a glass of rose before lighting a cigarette and speaking of her great creation, the British Royal Ballet.

"Our stars are spilled all over the world," she said without a trace of immodesty. "We make new ones each generation. We are an official national company after all, not a rent-a-car business.

One can only wonder what Dame Ninette would have done to the financial world had she gone into business instead of ballet. She certainly understands the psyche of success.

She left the legendary Ballet Russe of Serge Diaghilev in 1926 to start her own dancing school in Britain from which she hoped a ballet company would evolve. It did, five years later, as the Sadler's Wells ballet, named after the theater where it performed. Blessed with the great Alicia Markova as guest artist in its early days, the company survived and later flourished internationally, due in no small part to its triumphant first U.S. tour in 1949 under the auspices of impresario Sol Hurok.

It returns this summer for a six-week tour of North America, beginning on Tuesday with a week at Wolf Trap.

Ninette de Valois gained a "dame" in front of her name in 1951 and watched the Sadler's Wells become the Royal Ballet in 1956 before she retired in 1963 to devote most of her time to the ballet school associated with the company. She lives with her husband of 45 years, a doctor, in London.

Her greatest discovery as director of the company occurred over 40 years ago, when she first saw a thin, 14-year-old girl named Margot Fonteyn at her school. "I could do something with that face," she said at the time.

She did. Fonteyn was promptly ingested into the company and succeeded Markova in 1935. Later, she toured the English countryside with Sadler's Wells during World War II.

"We were lucky enough to have a war," Dame Ninette recalled. "We toured all the time. The Sadler's Wells was used during the war to house families from northern London who had been bombed out of their homes. We were built up during the war. People has no money, nothing else to do. The ballet became wildly popular then."

As one of the great figures of 20th-century ballet, Dame Ninette spans every generation of performer from Nijinsky to Baryshnikov. She danced for Diaghilev from 1923 until 1926, the last year as a soloist. She marveled at Nijinsky and his sister, Nijinska, herself a remarkable choreographer for Diaghilev, and watched the young George Balanchine join the Diaghilev troupe.

"Underneath it all, I knew I was never meant to be a dancer," she said. "I wasn't strong. I had an undetected case of polio on the left side of my body as a child, and it led to slipped discs and things like that later on. I really was delighted at my career change."

She left Diaghilev with great affection for the man and respect for his acumen and autocratic ways of bringing out the best in his performers.

"He was a great figure. He had wonderful taste," she said. "I admired him for his interest in English dancers. He predicted that the next ballet would come from England.

"He didn't want me to go. He was very sensitive," she continued. "Whenever anyone left, he always said, "They deserted me'-never 'They left me,'"

Dame Ninette came to Diaghilev after three years of French training, when at her mother's urging, she traded her real name, Edris Stannus, for an ancestral Huguenot name, and three years with Cecchetti, the Italian master held in high regard by Diaghilev. "I'm a lovely mixture," she concluded.

Most important to her own company, she had learned from Diaghilev when to be hard. "You mustn't crush the wrong people," she said. "To some people you must be sympathetic or you don't get anything out of them. You must be respected, yes, and trusted, but you mustn't go for popularity. That has absolutely nothing to do with it."

"All that we ask is that a dancer be disciplined," she continued. "People speak of the sacrifice in the life of a dancer. But ballet didn't limit my life at all. 'Limit' to me means that someone wants to do something very badly but is torn between something else. That was never the case with me."

Dame Ninette has done battle all her life with the entrenched arts establishment as well as the Philistines who favor other forms of entertainment altogether. While disconcerted at the drawing power and the quality of television today, she remains convinced, like a true Marxist, that her chosen cause will prevail sooner or later.

"I'm tired of being treated as the bastard child of theater," she said. "We've had to complete with the theater and the opera for years, and I like to think that we've arrived."

"I remember the first time that I was in Russia," she continued. "An old ballet master there compared the ballet and the opera in England to the Montagues and the Capulets.

"Television could be a marvelous medium for ballet, but they must perfect its production first," she said. "It has made the slowest progress. You must present effectively a three-dimensional world on the screen before it will work."

Of more concern to her today is the star system, which permeates ballet as it does baseball and movies.

"We love stars, but we must have them on our conditions, not theirs," she says. "We can't have a future if we don't give the future an opportunity. We're too dependent on superstars everywhere.

"The constant building is the hardest part of directing a company," she concluded. "You can't reply too much on the established stars. I'm a time watcher." CAPTION: Picture, Dame Ninette de Valois, by Donal F. Holway