 Eleanor Humphrey reporting from Maryland. John Landau, who produced James Cameron's Titanic and Avatar, two of the biggest films of all time, has died. He was 63, and paying tribute, Peter Jackson, who made the Lord of the Rings trilogy, described him as one of cinema's monumental figures. Titanic, which won John Landau an Oscar, was the first film to earn a billion dollars at the box office. He died of cancer. Jeannie Wolfe, a Hollywood entertainment reporter who interviewed him,