Emil Zatopek:
Major Achievements
First man to break 29:00 for 10k
1948 Summer Olympics: 10,000m Gold
1949 - June 11 to September 1 - Holds 10,000m World Record
1949 - October 22 - Holds 10,000m World Record
1950 European Athletics Championships: 5,000m Gold - 10,000m Gold
1952 Summer Olympics 5,000m Gold - 10,000m Gold - Marathon Gold and Olympic Record
1954 European Athletics Championships: 10,000m Gold - 5,000m Bronze
1954 - May 30 to August 29th - Holds 5,000m world record
1956 Summer Olympics: 5,000m Silver
1956 - July 15 - After seven years (during a period when distance running was improving at a fast pace) finally relinquishes the 10,000m world record.
2000 Honoured with the Pierre de Coubertin Medal (awarded to athletes who exemplify the "true spirit of sportsmanship" at the Olympics)
IAAF Hall of Fame
Other Achievements
1 hour Run WR - September 15 1951 to August 24 1963
20,000m WR - September 15 1951 to August 24 1963
25,000m WR - October 26 1952 to September 27 1955
WR - October 29 1955 to July 21 1965
30,000m WR - October 26 1952 to October 21 1956
Add that to the many humbling stories of his grace and kindness, and in my opinion, you get the greatest Athlete of all time.
And this just further proves my point:
http://rw.runnersworld.com/pdf/groat.pdf