[carom]

To me the greatest Olympian would best embody the fundamental principles of of Olympism:

1. Olympism is a philosophy of life, exalting and combining in a balanced whole the qualities of body, will and mind. Blending sport with culture and education, Olympism seeks to create a way of life based on the joy of effort, the educational value of good example, social responsibility and respect for universal fundamental ethical principles.
2. The goal of Olympism is to place sport at the service of the harmonious development of humankind, with a view to promoting a peaceful society concerned with the preservation of human dignity.
3. The Olympic Movement is the concerted, organised, universal and permanent action, carried out under the supreme authority of the IOC, of all individuals and entities who are inspired by the values of Olympism. It covers the five continents. It reaches its peak with the bringing together of the world’s athletes at the great sports festival, the Olympic Games. Its symbol is five interlaced rings.
4. The practice of sport is a human right. Every individual must have the possibility of practising sport, without discrimination of any kind and in the Olympic spirit, which requires mutual understanding with a spirit of friendship, solidarity and fair play.
5. Recognising that sport occurs within the framework of society, sports organisations within the Olympic Movement shall have the rights and obligations of autonomy, which include freely establishing and controlling the rules of sport, determining the structure and governance of their organisations, enjoying the right of elections free from any outside influence and the responsibility for ensuring that principles of good governance be applied.
6. Any form of discrimination with regard to a country or a person on grounds of race, religion, politics, gender or otherwise is incompatible with belonging to the Olympic Movement.
7. Belonging to the Olympic Movement requires compliance with the Olympic Charter and recognition by the IOC.

and follow the mission and role of the IOC

1. to encourage and support the promotion of ethics and good governance in sport as well as education of youth through sport and to dedicate its efforts to ensuring that, in sport, the spirit of fair play prevails and violence is banned;
2. to encourage and support the organisation, development and coordination of sport and sports competitions;
3. to ensure the regular celebration of the Olympic Games;
4. to cooperate with the competent public or private organisations and authorities in the
endeavour to place sport at the service of humanity and thereby to promote peace;
5. to take action to strengthen the unity of the Olympic Movement, to protect its inde- pendence and to preserve the autonomy of sport;
6. to act against any form of discrimination affecting the Olympic Movement;
7. to encourage and support the promotion of women in sport at all levels and in all
structures with a view to implementing the principle of equality of men and women;
8. to lead the fight against doping in sport;
9. to encourage and support measures protecting the health of athletes;
10. to oppose any political or commercial abuse of sport and athletes;
11. to encourage and support the efforts of sports organisations and public authorities to
provide for the social and professional future of athletes;
12. to encourage and support the development of sport for all;
13. to encourage and support a responsible concern for environmental issues, to promote sustainable development in sport and to require that the Olympic Games are held accordingly;
14. to promote a positive legacy from the Olympic Games to the host cities and host countries;
15. to encourage and support initiatives blending sport with culture and education;
16. to encourage and support the activities of the International Olympic Academy (“IOA”)
and other institutions which dedicate themselves to Olympic education.

as outlined in http://www.olympic.org/Documents/olympic_charter_en.pdf

I don't know who comes to mind first as my greatest Olympian, but Michael Phelps isn't it.

There are many, many problems with the IOC right now. I think I would have to look back into the history of the Olympic Games to find someone who best represents the Olympic ideals, because it would be very hard to truly live the Olympic ideals in todays world.