President Reagan, answering right-wing criticism that his response to the Soviet Union for shooting down a South Korean jetliner hasn't been tough enough, asked yesterday, "Short of going to war, what would they have us do?

"I know that some of our critics have sounded off that somehow we haven't exacted enough vengeance," Reagan said. "Well, vengeance isn't the name of the game in this."

Speaking via closed-circuit television to western Republican Party leaders at a Scottsdale, Ariz., conference preparing for the 1984 campaigns, the president said the U.S. response was "to make it plain to the world, as we have, that this is the Soviet Union against the world, not just the United States."

He noted that the United States was one of 13 countries which had victims among the 269 people killed Sept. 1 when Korean Air Lines Flight 007 was hit by a Soviet missile.

During a question-and-answer session Reagan said that the U.S. forces in Lebanon are experiencing a "perilous time," and said that when the multinational peace-keeping force was introduced into Lebanon the United States did not anticipate the outbreak of the civil war now occurring there.

"I don't think we were prepared for or believed there would be an outright civil war as seems to be going on right now," he said.

Later he added that he is "not planning a war there," and that while he has no plans to withdraw U.S. Marines from Lebanon he is "not planning to expand the forces there."

Reagan expressed confidence in the Lebanese army by saying that the American-trained force is "an excellent army and is doing a fine job." But the president added that, "We do not see any necessity at the moment or any good reason for withdrawing the multinational forces."

Earlier in the day the president attended a memorial service at the Washington Cathedral for victims of the attack on the South Korean jet, and then met with about 60 relatives and friends of victims, including the son of Rep. Larry McDonald (D-Ga.).

Reagan told them that the United States and other countries are trying to obtain reimbursement for the losses for families of the victims "of that terrible tragedy, that massacre" from the Soviets through international organizations.

"We are also trying . . . every way we can to see if we cannot get an end to the lying, an end to the defiance that the Soviet Union is presently voicing and see if we cannot eliminate the possibility of this ever taking place again," Reagan said.

He declared Sunday a national day of mourning for the victims.

The White House announced yesterday that Reagan will address the General Assembly of the United Nations on Sept. 26. Larry Speakes, the president's spokesman, said the president "believes that the overall world situation requires a statement at the highest level."

In the question-and-answer session, Reagan blamed Syria for the mounting fighting in Lebanon, saying that the Syrians, "undoubtedly influenced by the Soviet Union," have reneged on promises to withdraw from Lebanon if Israel witdraws its troops.

He also told the Republican Party leaders that he is proud of his record on women's rights, calling it "one of the best-kept secrets out of Washington." Citing his decision to seek to eliminate several gender-based distinctions in federal laws--which some Justice Department officials described as "cosmetic" and "inconsequential"--Reagan said he knows some people believe in "equality even when it penalizes women . . . . I don't believe in that."

Asked what he is doing to help Hispanic Americans, Reagan, who is scheduled to attend a half-dozen events for Hispanics next week, said he has been making efforts on behalf of Hispanics and countries in Latin America.

Despite the success of those efforts with some Hispanic Americans, he said that several major Hispanic groups are "lined up with Democrats. So I don't think I'm going to be able to make much of a dent in them."

Before Reagan spoke to the party officials yesterday, Speakes said that Soviet charges that the South Korean airliner was involved in espionage were "absurd," and said a news conference yesterday by Marshal Nokolai Ogarkov, chief of staff of the Soviet armed forces, failed to "provide us or the rest of the world with answers."

Meanwhile, Defense Secretary Caspar W. Weinberger said he suspects the reason the Soviet Union is prohibiting Japanese ships from searching for the downed jet is because the Soviets soon will "manufacture" evidence that the jetliner was a spy plane.

Weinberger, who made the comment in a television interview, said the Soviets want to "come up with some black box dripping with seaweed and claim that the Koreans pilot was a spy or some nonsense."

The White House also announced yesterday that a nuclear-powered Trident missile submarine will be named the USS Henry M. Jackson, in honor of the late Democratic senator from Washington.