"It's a wonderful day for you and your families and Nancy and myself, and I was just thinking," President Reagan said yesterday to an expectant East Room audience, "sometimes it's fun to be president."

Everybody laughed at the joke, especially since yesterday's "fun" was presentation of the nation's highest civilian award, the Presidential Medal of Freedom, to 12 winners, including entertainers Frank Sinatra and Jimmy Stewart, conservationist and former Smithsonian secretary S. Dillon Ripley and former U.N. ambassador Jeane Kirkpatrick.

"Each of you achieved that hardest of all things to achieve in life, something that will last and endure and take on a life of its own," Reagan told the recipients, who also included undersea explorer Jacques-Yves Cousteau, World War II hero Gen. Albert Coady Wedemeyer, former test pilot Gen. Chuck Yeager and educator and philosopher Sidney Hook. "More than you'll ever know, this world would have been much poorer and a dimmer place without each of you."

Presentation of the medals, a five-pointed white star with a blue center, climaxed a luncheon hosted by Reagan and his wife, Nancy. Four of the awards were posthumous and went to jazz pianist Count Basie, educator and ambassador Jerome Holland, NASA administrator and educator George Low, and television anchorman and correspondent Frank Reynolds.

A 13th recipient, Mother Teresa, the Yugoslavian-born missionary who has spent 30 years working with India's sick and dying, was unable to attend. Her medal will be presented later.

Reagan was unabashedly lavish in his praise, and most of the recipients seemed to be in a state of awe as they were singled out for recognition. A ruddy Sinatra, 67, who like Stewart, 77, is a close friend of the Reagans, almost looked to be blushing as he heard himself described as "without peer."

"His love of country, his generosity for those less fortunate, his distinctive art and his winning and compassionate persona make him one of our most remarkable and distinguished Americans, and one who truly did it his way," Reagan said.

Of Stewart, the president said: "His typically American characters -- boyish, honest and kind -- mirror the Jimmy Stewart in real life -- an American boy who grew to a glorious manhood, but never lost his sense of wonder or his innocence."

The president praised Ripley, 71, for making the Smithsonian Institution "one of the greatest museums and centers of learning on earth," while Kirkpatrick was described as "an endlessly articulate spokeswoman for the moral and practical benefits of freedom."

Count Basie's award was accepted by his son, Aaron Woodward, and Low's by his widow Mary. Laura Holland received her late husband's medal and heard Reagan describe him as committed to "improving the lives of others, particularly his fellow black Americans, and to working for peace."

Reynolds, Reagan told the newsman's widow Henrietta, earned the respect of his colleagues and the trust and admiration of the American people for "his commitment to the truth, his unfailing sense of fairness."

Yeager, said Reagan, was "a hero in war and peace" who, on Oct. 14, 1947, in a rocket plane named "Glamorous Glennis" after his wife, "became the first human being to travel faster than the speed of sound, and in doing so, showed to the world the real meaning of 'The Right Stuff.' " After the ceremony ended, the first thing the beaming Yeager did was walk to the table where Glennis Yeager sat and hand her his medal.