Well, the worst actor of the year goes to "Bernard Hopkins" in his fight against Roy Jones. If you missed it, congratulations. If you saw it, even for free, I'd still say those who televised it on PPV owe you some money. Bernard going down from rabbit punches that couldn't have hurt a child was pathetic. Then the act with the low blows. I heard his statement as the following: "You can see I'm just as shot as Roy Jones."
As far as movies are concerned, I don't think there is a single greatest actor or actress on the planet. Genre's show Al Pacino and Robert De Niro as the best gangster actors. (For De Niro, see "Raging Bull" and "Taxi Driver" for roles outside of the gangster genre.) (Pacino lit up the screen is "Serpico" and "Dog Day Afternoon") Meryl Streep is probably the best character actor I've ever seen along with Dustin Hoffman. Marlon Brando was a gem and could do mostly anything. Phillip Seymour Hoffman seems to be a perfect actor. Too many to mention. As tough guys go, Micky Rourke has no peers. The list goes on and on and my opinion can change from day to day depending on the movies I see.