OpenGL vs DirectX

Dear Programmers:
I don't wish to create a massive thread, but I am a newby to 3D programming
(but not Delphi) and would like to know which is the most
popular/common/best way to go with Delphi programming (OpenGL or DirectX) ?
Many thanks;

Douglas Franz Colman
ph: +61-2-6773-3149
fx: +61-2-6773-3312
Univ. of New England,