When Pope John Paul II plunged into the crowd on the South Lawn of the White House yesterday, actor Gregory Peck got in a private word; Baltimore businessman John Venoitti kissed the pontiff's ring, and June Kuczynski from Detroit got her picture taken getting a kiss from His Holiness.

It was the kind of a democratic happening at which cardinals of the church and senators of the government were outmanuevered by Irish labor leaders, a Methodist judge and a Jewish car dealer, in their enthusiasm to greet the Polish Pope.

There were disappointments, to be sure. TV talk show host Phil Donahue said, "I couldn't get near him." Neither could Sister Magdalena from the Korean Catholic Church on Michigan Avenue NE, who at least got to see the pope, which was more than she could do earlier at St. Matthew's Cathedral.

And Baltimore City Councilman Dominic (Mimi) DiPietro shoved his way to the front of the crowd, only to give up a chance of kissing the pope's ring in favor of "a handicapped lady the pope wanted to see." DiPietro said he had met both President Carter and the pope before, but "the pope didn't remember me."

"The president did, though," he boasted.

The first visit of a pope to the White House was divided into three events, which took up most of the afternoon. The arrival ceremony on the North Lawn was witnessed by about 3,000 persons, including members of the Supreme Court, Congress and the Cabinet.

The longest and last event, on the South Lawn, was attended by more than 6,000 persons, 5,835 of whom had been invited by the White House. Most of the invitations were addressed to adults, but a number of guests showed up with children, and as one White House police officer said, "I wasn't going to turn them away."

The guest list ran from Ernest Abate to Irene Zurnelli, with 54 Murphys in between. It included four governors, among them John Dalton of Virginia, five big-city mayors, leaders of half a dozen labor unions, black groups, state and national Democratic organizations, judges, educators, entertainment and sports stars and, according to one guest, "lots of people who are on the mailing lists of the Carter-Mondale reelection committee.,

Spotted on the South Lawn were Muriel Humphrey, Averell Harriman, Arthur Goldberg, Jack Valenti, Carl Yastrzemski, Clarence and George Meany.Meany, in a wheel chair pushed by his heir apparent, Lane Kirkland, was sought out by the pope for personal greetings.

Also on the list of invitees were a flock of the Kennedy clan, including Ethel, Joseph Kennedy Jr., R. Sargent Shriver and his wife, and Pat Kennedy Lawford.

Two of the best known Catholics in Congress, House Speaker Thomas P. (Tip) O'Neill, and Sen. Edward M. Kennedy, were among the no-shows, but both men had greeted the pope in their home state of Massachusetts on Monday.

After the 20-minute ceremony on the front lawn, three members of an impromptu Polish congressional caucus -- Sen. Edmund S. Muskie (D-Me.) and Reps. Edward J. Derwinski (R-Ill.) and Clement J. Zablocki (D-Wis.) -- broke out in a song, "Sto Lat," meaning "100 years," in the pope's native language. The amateur rendition generated a smile of recognition from the pope.

The unexpectedly warm, gorgeous autumn day moved D.C. Del. Walter E. Fauntroy, a Baptist minister, to point heavenward and quip, "I'm now convinced that the pope not only is in sales, but he's also in management."

The day was made more festive by the colorful garb of some of the guests. Wehn the wind whipped up periodically, the magenta sashes on the robes of the cardinals and Vatican aides flashed brilliantly against the blue sky. The pope's own white cassock flapped as though it had wings, and at one point in the pontiff's speech, President Carter reached out to hold it down.

Betleen the two public events on the lawns, the pope was a guest at a private reception inside the White House. Calvin Carter, the president's cousin, said it was a great success. He said the president and the pope seemed to have a lot in common and "I think they got along very well."

The easiness of the relationship between the pope and the president was evident to the crowd, as Carter said of the pope, "He comes to us as a pastor, scholar, poet and philosopher, but I think primarily as a pastor."

"You'r right, "offered the pope, as the crowd laughed.

"He's decided not to dispute the word of the president," Carter, also laughing, went on.

By the time the afternoon ended with the pope joking that he had received "permission" of the president to bless the crowd, even some members of the blase press corps put down their cameras and pens long enought to cross themselves.

And as the pope and the Carters wolked up the stairs to return to the White House, Mrs. Carter appeared to join in the chant, "Long Live the Pope."