Hi there , i'm a planning to develop a 2D game for PC platform and later port it to some console if time permits. Now i have to take a decision between the two API's. I know that if develop on Directx i can only port to XBOX 360, and at the same time if i choose to develop on openGL i guess i have options like porting to PS2,PSP , mobiles and even WII(of course with major modifications).i Want Your advice on the two API's and which to decide for now

You're only partially right. With DirectX, you're stuck with Windows and XBox/X360. With OpenGL you can hit up Windows, Linux, Mac, PS2/PS3, Wii, and any other platform that uses the API, not just consoles! I also find that OpenGL is much easier to learn and understand. A lot of DirectX code is so difficult to follow that it's a pain to rework somebody else's code.
-Sephiroth