She has played queens in two movies this year to great success, but if you ask Helena Bonham Carter her preference in monarchs -- she would rather play the king!

It's not hard to imagine. Gender-bending performances have worked well in contemporary tales for Hilary Swank ("Boys Don't Cry") and Felicity Huffman ("Transamerica").

But for Bonham Carter in "The King's Speech," currently in theaters and earning Oscar buzz, being the king would have been more difficult to pull off given the film is set in the early 20th century and the years leading up to World War Two.

Still, she says the plum role in "The King's Speech" was that of stammering King George VI, which was snagged by Colin Firth. Bonham Carter plays his wife, Queen Elizabeth the Queen Mother.

"That was definitely the part," she told Reuters in a telephone interview from the home in London she shares with long-time companion, director Tim Burton.

"Both men's roles (in the movie) are fantastic, and it is really about their friendship. It's adapted from a play, and anything that started as a play is much more actor oriented."

The other of the "men's roles" is Lionel Logue, portrayed by Geoffrey Rush, who is King George's speech coach in the movie, which is based on real events.

It's not that Bonham Carter is complaining. In fact, she is happy to have worked in the movie, and as much as Firth and Rush are winning award attention in their roles, she too has gained the critics' eye playing the Queen Mum.

"I think she was the ultimate supporting wife," Bonham Carter said of her character.

PROBLEMS AND COMPASSION

"The King's Speech" covers a period of George VI's life when he unexpectedly ascended to the throne after his father, George V, died and his brother, Edward VIII, abdicated in order to marry divorced American socialite Wallis Simpson.

For George VI, however, becoming the head of state at a time when Britain was on a path toward war with Germany was a problem because the British people needed a leader in whom they could be confident. But George VI had an awful stammer and was terrified of public speaking.

His wife hired a quirky Australian speech coach to help him improve, and the movie covers the ups-and-downs of their teacher-student relationship.

Bonham Carter's parents both suffered debilitating illnesses, and she said she drew from her experiences with them to portray the Queen Mum. "My father was very ill. For years, my mother tried every single route (to improve his health). She didn't stop at anything, and you don't. There's no door that goes unopened," she said.

She also called her parents "compassionate people" and said she was the product of "a marriage that worked."

In her own life, Bonham Carter has partnered with director Burton for a decade and the pair have two young children. He directed Bonham Carter in her other "royal" role of 2010, the manic Red Queen in his 3D movie "Alice in Wonderland.

She joked that if Burton is complaining or whining around their home or having a difficult time overcoming a problem, "I just tell him to get on with it and quit moping around."

But upon quick reflection, she changes her story.

"I hope I'm compassionate," she said. "Living with a director -- the stress of living with a director and having to answer all the financial pressure -- I think we both need to be supportive of each other."