1) What makes this person famous?

He's still the most recognizable man on earth. And over forty years after he burst onto the scene as a gold-medal winner at the 1960 Rome Olympics, Muhammad Ali remains a magical figure, known and loved throughout the world.

2)Which one particular thing did they do that shot them to fame?

As a boxer, Muhammad brought unprecedented speed and grace to his sport, while his charm and wit changed forever what the public expected a champion to be. His accomplishments in the ring are the stuff of legend – two fights with Sonny Liston, where he proclaimed himself "The Greatest" and proved he was; three epic wars with Joe Frazier; the stunning victory over George Foreman in the Rumble in the Jungle; and dethroning Leon Spinks to become heavyweight champion for an unprecedented third time. But there was always far more to Muhammad than what took place in a boxing ring.

3)What makes this person considered "crazy"?

Muhammad's life and career have been played out as much on the front pages of newspapers as on the inside sports pages. His early embrace of the Nation of Islam and his insistence on being called Muhammad Ali instead of his "slave name," Cassius Clay, heralded a new era in black pride. His refusal to be inducted into the United States Army anticipated the growing antiwar movement of the 1960's. His willingness to stage his much-promoted and publicized fights in such far-flung locales as Kinshasa, Manila, and Kuala Lumpur signaled a shift from superpower dominance toward a growing awareness of the developing world.
Daring to go against political policy to help people in need, Muhammad has made goodwill missions to Afghanistan and North Korea; delivered sorely-needed medical supplies to an embargoed Cuba; traveled to Iraq and secured the release of 15 United States hostages during the first Gulf War; and journeyed to South Africa to meet Nelson Mandela upon his release from prison.

4)Do you think think this person is truly a "genius"? Why?

For his humanitarian efforts, Muhammad has been the recipient of countless awards. In addition to being honored by Amnesty International with their Lifetime Achievement Award, the Secretary-General of the United Nations bestowed upon him the citation of United Nations Messenger of Peace. In Germany, he was honored with the 2005 Otto Hahn Peace Medal for his involvement in the U.S. civil rights movement and the United Nations. He was also named the International Ambassador of Jubilee 2000, a global organization dedicated to relieving debt in developing nations. Other honors include an Essence Award, an XNBA Human Spirit Award and recognition from the National Urban League; 100 Black Men; Givat Haviva; the Oleander Foundation; The National Conference of Christians and Jews; Time magazine; and former President Jimmy Carter, who cited Muhammad as "Mr. International Friendship." Ever the entertainer, Muhammad has appeared in several motion pictures, including the big-screen adaptation of his first autobiography, The Greatest, playing himself. His life has been the subject of numerous films, including the Academy Award-winning documentary When We Were Kings and the Michael Mann's biopic, ALI, starring Will Smith. Muhammad also starred in Freedom Road, and made guest appearances on numerous popular television series ranging from Diff'rent Strokes to Touched by an Angel. He also starred on Broadway in the musical, Big Time Buck White, and recorded a popular album, I Am The Greatest!

credits: http://www.ali.com/