The makers as you can read tried the white box program.
As to software, you can get a refund for the OS. There are no other softwares on the machine worthy of note since (at least here in the US) they can't force the OS on you. The refund process is a little tedious but people do that.
http://www.google.com/search?hl=en&lr=&q=XP+REFUND
Be sure you want to do this since it also can make hardware support impossible. Let's take the instance your USB ports don't work after you install your OS. If you make the common mistake they won't. You call for repair and the tech finds the issue and then hands you the bill. Be sure you are ready for this event.
Bob

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