Peter Ustinov, 82, the jolly and jowly Academy Award-winning actor once described as a jack-of-all-arts for his work as a director, writer and raconteur, died of a heart ailment March 28 at his home overlooking Lake Geneva, in Switzerland. He had diabetes.

Mr. Ustinov, born in London to parents of Russian and German heritage, was known for his versatile mimicry. He was fluent in French, German, English, Italian, Russian and Spanish and passable in several other tongues.

A burly and sometimes-bearded six-footer, Mr. Ustinov seemed totally uncategorizable in his abilities. A high school dropout, he acted in, directed or produced about 100 films, wrote more than 20 books, filled countless newspaper columns with observations about his world travels, was an accomplished composer and became a children's advocate for the United Nations.

Above all, he was wide-ranging in his interests, from art to politics to economics. He could expound on nearly any topic at length -- and in any accent.

"Peter Ustinov is not an actor," Michael Kernan once wrote in The Washington Post. "He is a cast of characters."

Mr. Ustinov won two Oscars for best supporting actor, playing the owner of the gladiator school in "Spartacus" (1960) and a loveable chump in Jules Dassin's jewel-heist caper "Topkapi" (1964).

His range also included the riotously stressed Arab hotel owner in "Hotel Sahara" (1951); the cruel emperor Nero in "Quo Vadis?" (1951); a comic convict in "We're No Angels" (1955) with Humphrey Bogart and Aldo Ray; an Australian layabout in "The Sundowners" (1960); the ship captain in Herman Melville's good-vs.-evil morality story "Billy Budd" (1962), which he also directed; and Agatha Christie's Belgian dandy and detective Hercule Poirot in a series of films beginning with "Death on the Nile" (1978).

As a television actor, he won three Emmy Awards, playing a noted English lexicographer in "The Life of Samuel Johnson" (1958); the philosopher Socrates in "Barefoot in Athens" (1966); and an elderly Jewish man on Long Island, N.Y., who has a relationship with a black youth in "A Storm in Summer" (1970) .

To generations of young listeners, he might be best remembered for his narration of "Peter and the Wolf." With Herbert von Karajan conducting Prokofiev's music, Mr. Ustinov won the 1959 Grammy Award for best recording for children.

He also provided voices on a record of "Babar the Elephant."

For decades, he was a goodwill ambassador for UNICEF, the U.N. children's agency.

As he was feted as an international movie star and humanitarian, he liked noting the foibles of formal etiquette.

Before his knighthood ceremony in 1990, he received an invitation from Buckingham Palace. "The invitation said, Delete whichever is inapplicable: 'I can kneel -- I cannot kneel.' But there was nothing for those who can kneel but not get up," Mr. Ustinov said.

Peter Alexander Ustinov was born amid privilege and eccentricity. His father was a journalist of German-Russian origin who was fond of wearing a monocle for affect. His mother, an artist whose work was widely exhibited, was of noble Russian descent.

As a child, Mr. Ustinov often practiced replicating the voices and facial expressions of his parents' worldly houseguests, including Ethiopian Emperor Haile Selassie. He later brought the same gift to the schoolyard, where he favored classmates with imitations of the schoolmaster.

He did not otherwise enjoy school. He said he was once asked to name the world's greatest composer. He told an interviewer years later: "I was heard to say Mozart and I was told Beethoven and I was heard to say, 'I prefer Bach to Beethoven' and I had to write 'Beethoven is the greatest composer' 100 times. This taught me a lesson about adult stupidity -- one which ordinarily would have taken me longer to learn."

He found himself far more interested in the theatrical world. He studied acting under Michel Saint-Denis at the London Theatre Studio. In 1940, he wrote his first play, "House of Regrets," about czarist Russian exiles living in London. The show was acclaimed by the drama critic James Agate, a major step in his career.

During World War II, he served in the British army and also tended to his career. He acted in and wrote the wartime film "The Way Ahead" (1944), directed by Carol Reed. He also mounted more productions of "House of Regrets" as well as his second play, "Blow Your Own Trumpet," about deluded habitues of a cafe in South London.

In 1946, at age 25, he directed his first film, "School for Secrets" starring Ralph Richardson as a scientist helping to develop radar technology to defeat the Nazis. He also directed the comedy "Vice Versa" (1948) with Roger Livesey as a businessman who magically trades places with his schoolboy son. He continued his rise as an actor on stage, starring opposite John Gielgud in a production of "Crime and Punishment."

Not all his projects were deemed successes. There was some critical backlash at his ubiquity and perceived indulgences as an artist. Some reviewers wanted him to slow down, polish and cut his work.

Mr. Ustinov, however, said his job was "to ask questions, not to answer them" as he explored such varied topics as religion ("The Indifferent Shepherd") and military life ("The Love of Four Colonels"). In "Four Colonels," which played for two years in London's West End theater district, he said his experience in the army led him to "appreciate to the full the limited magnificence of colonels, those exalted beings who need only reserve their politer smiles for generals, but who can lavish their frowns on the drab little worlds they rule."

Most critics agreed that Mr. Ustinov's verbal and physical pomp came together successfully in "Quo Vadis?" one of his first Hollywood acting roles and for which he won a Golden Globe for best supporting actor. He stood out in the otherwise wooden spectacle that starred Robert Taylor and Deborah Kerr, and he was offered more acting parts in American movies.

He continued writing plays, notably "Romanoff and Juliet" (1957), about a romance between the children of Russian and American diplomats during the Cold War era. "At the age of 4 with paper hats and wooden swords we're all generals," one character says. "Only some of us never grow out of it."

In an essay about Mr. Ustinov for the Dictionary of Literary Biography, Audrey Williamson wrote of his career: "His mockery is of all sides and without allegiance, if one excepts allegiance to humanity as a whole. . . . In a world at best maintaining a precarious peace, Ustinov, the traditional serious clown, is a valuable reminder of civilization's most conspicuous and recurring follies."

Mr. Ustinov moved to Switzerland in 1971 and began his career with UNICEF and UNESCO, the U.N. Educational, Scientific and Cultural Organization. "My interest," he wrote in "Dear Me," his 1977 memoir, "grew out of a dissatisfaction with a life of the merely amusing, of the merely diverting."

His autobiography was written as a conversation with himself complete with interruptions and self-corrections. He told a reporter that he "shall possibly write another book and call it 'P.S.' and perhaps another. . . . After all, it is a show business tradition, established by [Australian opera star] Nellie Melba, who started out her career by giving farewell concerts."

He wrote novels and books of his collected witticisms and continued acting until his death.

In choosing parts, he once said he never felt a need to be sympathetic. "How do you know that I'm not a disagreeable person and the trouble comes from the agreeable roles that I am forced to play?" he said.

"Actually, I rather enjoy playing Nazi generals and believing I'm right. It gives one the possibility of tilting at something one dislikes. If you're an actor, you've got to be a devil's advocate," he said.

His marriages to Isolde Denham and Suzanne Cloutier ended in divorce.

Survivors include his third wife, Helene du Lau d'Allemans, whom he married in 1972; a daughter from his first marriage; and three children from his second marriage.

Actor Peter Ustinov is congratulated by actress Sophia Loren, who holds his Oscar for best actor in a supporting role for his performance in the 1964 film "Topkapi."