The following list is biased from The Nixon Foundation:
In 1973, President Nixon ended the draft, moving the United States military to an all-volunteer force.
Responding to rising concern over conservation and pollution, President Nixon founded the Environmental Protection Agency, and later oversaw passage of the Clean Air Act, the Clean Water Act, and the Mammal Marine Protection Act.
By appointing 4 Supreme Court justices; Chief Justice Burger, Harry Blackmun, Lewis Powell, and William Rehnquist, who later became Chief Justice, President Nixon ushered in an era of judicial restraint.
Dedicated a $100 million to begin the War on Cancer, a project that created national cancer centers and antidotes to the deadly disease.
Signed Title IX in 1972, preventing gender bias at colleges and universities receiving federal aid, opening the door for women in collegiate sports.
President Nixon initiated and oversaw the peaceful desegregation of southern schools.
Welcomed the astronauts of Apollo XI safely home from the moon, eventually overseeing every successful moon landing.
President Nixon was a great proponent of the 26th Amendment, extending the right to vote to 18-20 year olds, lowering the voter age from 21.
President Nixon effectively broke the back of organized crime, authorizing joint work between the FBI and Special Task Forces, resulting in over 2,500 convictions by 1973.
President Nixon ended the policy of forced assimilation of American Indians, returned sacred lands, and became the first American President to give them the right to tribal self-determination.
President Nixon participated in the Strategic Arms Limitation Talks (SALT) with Soviet Secretary General Brezhnev in 1972 as part of the effort to temper the Cold War through diplomatic détente.
Signed the Anti-Ballistic Missile (ABM) Treaty, helping to calm U.S.-Soviet tensions by curtailing the threat of nuclear weapons between the world’s two superpowers.
President Nixon was the first President to visit the People’s Republic of China, where he issued the Shanghai Communiqué, announcing a desire for open, normalized relations. The diplomatic tour de force brought more than a billion people out of isolation.
Signed the Paris Peace Accords in 1973, ending U.S. involvement in the Vietnam War.
Announced a groundbreaking foreign policy doctrine in 1969 that called for the United States to act within its national interest and keep all existing treaty commitments with its allies.
Established a new relationship with the Middle East, eliminating Soviet dominance in the region and paving the way toward regional peace.
Brought home the POWs from Vietnam, and hosted the largest reception in White House history in their honor.
Initiated Project Independence in reaction to the oil embargo of 1973, which set a timetable to end reliance on foreign oil by 1980.
In 1970, President Nixon avoided a second Cuban Missile Crisis involving a Soviet submarine base by adhering to his policy of hard-headed détente, an active rather than passive form of diplomacy.
Supported Israel with massive aid in the 1973 Yom Kippur War, which Prime Minister Golda Meir later said saved her country.
[source : Richard Nixon's Top Domestic and Foreign Policy Achievements, Nixon FOundation, http://nixonfoundation.org/10-policy-achievements.php]
Not exactly great.
As for that last foreign policy achievement, saving Israel, if he had not saved Israel then we may not have had 9/11 and all the PNAC wars since!!
So rather than being an achievement, saving Israel was just another Nixon blunder, along with escalating the Vietnam War, bombing Cambodia, and toppling Allende in Chile to give us Pinochet.