PS2 Street Fighter pads on Xbox

So I one 5th place in an Art contest. Hooray!

I win two pS2 Street Fighter controllers. I pick Ken and Akuma (But get sent Chun Li instead but nevermind)

I bought PS2 to Xbox converter which runs fine on the Offical Dual Shock. And when my pads finally arrive the buttons dont work. Only the D pad and start and select.

What converter do I need to run these suckers on my Xbox???

Also have people had the same problem with PS2 to USB converters? Or would it be worth picking one up to use my controllers on my PC?

Any help would be fantastic