Dame Helen Mirren has been named best actress at the Academy Awards for her performance in The Queen
"All kids love to get gold stars, and this is the biggest and the best gold star that I have ever had," she said.
Martin Scorsese's crime drama The Departed won four Oscars, including best picture, while the film-maker won his first best directing honour.
Alan Arkin won best supporting actor for Little Miss Sunshine, which also picked up best original screenplay.
Jennifer Hudson was named best supporting actress for her first film role, in the musical Dreamgirls.
The adapted screenplay prize went to the script for The Departed, which also won for editing.
The best actor Oscar went to Forest Whitaker, who had been favourite to triumph for his performance as the Ugandan dictator Idi Amin in The Last King of Scotland.
'Pretty good shot'
Dame Helen had also been overwhelming favourite to add the best actress Oscar to a substantial awards haul that has included a Bafta, Golden Globe and Screen Actors Guild prize.
She plays Elizabeth II in the British movie about the Royal Family's reaction to the 1997 death of Princess Diana.
Bookmaker William Hill started paying out last week on bets on her victory, with other firms agreeing she was the strongest ever Oscars favourite.
Academy Awards host Ellen DeGeneres had joked to the audience early in the ceremony: "It's exciting because you don't know who's going to win - unless you're British, and then you know you've a pretty good shot."
Accepting her award, Dame Helen said: "For 50 years and more, Elizabeth Windsor has maintained her dignity, her sense of duty and her hairstyle.
"If it wasn't for her, I most certainly wouldn't be here - ladies and gentlemen, I give you the Queen."
Scorsese had previously been nominated as best director but lost out on five occasions, for classic movies including Raging Bull and Goodfellas.
"Could you double-check the envelope?" he joked as he collected his award.
He went on: "So many people over the years have been wishing this for me - strangers. I walk in the street and people say something to me: 'You should win, you should win.'"
'Billion viewers'
The best animated feature film Oscar was awarded to Happy Feet, while Germany's Das Leben der Anderen (The Lives of Others) was the best foreign language film.
The Spanish-language dark fairytale Pan's Labyrinth won three Academy Awards, for cinematography, art direction and make-up.
Environmental film An Inconvenient Truth was best full-length documentary, and Melissa Etheridge's I Need to Wake Up - one of the tracks from that movie - won best original song.
Dreamgirls picked up a second award for sound mixing, while Letters from Iwo Jima was rewarded with the best sound editing prize.
DeGeneres opened the ceremony in Los Angeles' Kodak Theatre by telling nominees "everything is on the line for you".
She urged the stars not to worry about whether they would win and the pressure of an acceptance speech in front of their peers, adding: "I'll tell you what you should worry about - there's a billion people watching right now."
First published on the BBC Website|