Sir Ridley Scott

Ridley Scott has a huge list of production under his belt as can be seen from the link. He has produced and directed many big budget films including, Gladiator, Kingdom of Heaven, Black Hawk Down, Hannibal, etc. His newest movie that is coming out this year is American Gangster, which is about a drug lord that smuggles heroin into Harlem during the 70's hiding the stashes inside the coffins of American soldiers' coffins, returning from Vietnam.

Robert Zemeckis

The link that is posted gives a quick biography of Robert Zemeckis and this link gives the filmography of all his works as a director, producer, screenwriter, and executive producer. http://movies2.nytimes.com/gst/movies/filmography.html?p_id=117906&mod=films He has been involved in such movies as, House of Wax, Castaway, Monster House, The Polar Express, and Forrest Gump. Robert has also won many awards and this link lists some of them. http://movies2.nytimes.com/gst/movies/filmography.html?p_id=117906&mod=awards

This is what the author of the article said about the movie I Wanna Hold Your Hand, which Robert directed, "despite the film's low budget, it demonstrated Zemeckis' ability to combine credible live-action sequences with elaborate special effects devices." This shows his talent as a true director.