For which film did Russell Crowe win the Oscar for Best Actor?

For which film did Roberto Benigni win the Oscar for Best Actor? Who won the Oscar for Best Actor for 'American Beauty'? For which film did Kevin Spacey win the Oscar for Best Actor? Who won the Oscar for Best Actor for 'Gladiator'? Who won the Oscar for Best Actor for 'Training Day'? For which film did Denzel Washington win the Oscar for Best Actor? Who won the Oscar for Best Actor for 'The Pianist'? Who won the Oscar for Best Actor for 'Mystic River'?