If Kitty Carlisle Hart tried to see all the productions of all the plays her late husband Moss wrote with George S. Kaufman, she'd probably be on the road 365 days a year and setting a record for most high-school auditoriums visited by a single human being.

"Everybody I know was in a Kaufman and Hart play," she said last weekend between an Arena Stage matinee of "The Man Who Came to Dinner" and a State Department get-together for the Kennedy Center Honorees. She recalled asking a friend, "Did you ever act in the theater?" and getting the reply, "Yes, once. I played Essie in 'You Can't Take It With You' in high school." The friend was Jacqueline Onassis.

The number of current Kaufman and Hart productions is "staggering," according to Hart, the former opera and musical comedy singer who now chairs the New York State Council on the Arts. Statistically, "You Can't Take It With You" is the most produced of the plays, followed by "The Man Who Came to Dinner" and "Once in a Lifetime."

"I can't tell you in terms of actual numbers," said Hart, 63. "I can only tell you that's the way they go because of the royalties, you know . . . . And it doesn't vary. It never seems to go down. They are good plays in a way much more important than either Kaufman or Hart thought they would be. Only posterity can tell you if you are going to be a great playwright or not, and I guess posterity is telling them that they wrote plays that are going to last."

Alexander Woollcott, the rotund critic and radio pundit who organized the Algonquin Round Table and served as the inspiration for "The Man Who Came to Dinner," died in 1943, three years before the Harts married. By then, the Round Table group was no longer a group, and Moss Hart (considerably younger than Kaufman, Woollcott, Robert Benchley and other Round Table stalwarts) had never been a member in any case. But he continued to mix with many of the same people and with a succeeding generation of literary and show-business figures noted for their party-giving and early jet-age jet-setting.

"It may be that the young people today are as witty, as amusing, as funny -- or take the trouble to do the kinds of things that they did then," said Hart, "but I don't believe it. They wrote wonderful letters to each other. We had parties that we used to rehearse for days. I mean we once had a party for [agent] Irving Lazar's 50th birthday, and Irving came to town for his party and he said after two days in New York he was the loneliest man in town because he couldn't see any of his friends. We were all busy rehearsing for his party."

Moss Hart, according to his widow, "was a very impatient man. He'd plant a tree in the morning and expect it to give shade in the afternoon. And he bought houses everywhere. He was a tremendous collector . . . He bought a farm in Bucks County, [Pa.], which sat in the middle of a cornfield. There wasn't a tree or a bush on the place. Moss planted 2,000 fully grown pine trees, and George Kaufman came over one day, took a look at the place, and said, 'Well, Moss, it's exactly what God would have done if he'd had the money.'"

The Kaufman-Hart partnership dissolved after "George Washington Slept Here" in 1940. "Moss wanted to write alone, and George understood that," said Kitty Hart. Moss Hart went on to write the musical "Lady in the Dark" (with a score by Kurt Weill and Ira Gershwin), a series of plays including "Winged Victory," the screenplay for "Gentleman's Agreement," and the autobiographical "Act One," the Cinderella story of his Bronx boyhood and his first experience as a Broadway playwright (collaborating with Kaufman on "Once in a Lifetime").

The writing of "Act One" can be traced to Moss Hart's extraordinary insomnia, according to Kitty Hart. After their marriage in 1946, "he would go to bed and he'd say to me, "Tell me the story of your life,' and I was like Scheherezade -- I told him the story of my life every night and he would fall asleep. And then I ran out of the story of my life, so I said, 'Now you tell me the story of your life.' And I laughed and I cried and I said, 'You've got to write it down.'"

The author resisted the idea at first. "He used to say, 'Oh my God, there's no money in it. It's a self-indulgent thing. Where will the grocery money come from?' And I made him do it. I said, 'I'll scrub floors, I'll do anything, but you've got to finish it.' So he did." He died in 1961, only two years after the book was published and year after directing "Camelot" on Broadway.

During their 15 years together, she scaled down her own career as an actress and singer to occasional brief engagements and her once-a-week duties as a panelist on "To Tell the Truth." After his death, "I did everything anybody asked me to do. I was on all these boards. I was on more boards than you could shake an agenda at." Then "one thing led to another" and Nelson Rockefeller named her vice-chairman of the state arts council. Five years ago, Hugh Carey elevated her to chairman, in which unsalaried role she oversees an 88-person staff and a $30-million budget.

Their daughter Cathy is an intern at New York hospital, but the theatrical tradition may be carried on by their son, songwriter Christopher Hart. And Kitty Carlisle Hart's own show-business career has revived, in a sense, with the return of "To Tell the Truth," a commitment that stretches back (with interruptions) nearly 25 years.

She can also be seen, from time to time, as the ingenue in the Marx Brothers' "A Night at the Opera." And 45 years later, she will gladly sing a few bars of "Alone," her swooning lament to Allan Jones in the opera-within-the-movie.

When "A Night at the Opera' began to reappear in the late '60s, Hart attended a showing with great apprehension. "There were a bunch of kids going in, and I thought, 'Oh, they're going to make fun of me because I was in the straight part. They're going to make fun of the love scene, and I'm going to be embarrassed and Oh Golly!"

But her fears were unjustified. "Nobody made rude remarks and catcalls and all the things I was expecting. They were perfectly happy with all those love scenes."