Why not linux 
Never used Linux before. Yes, paid for my Windows licenses, sorry. Rather not try to crack 7 and again it's the case of legitly using these systems for business purposes other than mining potentially that I want to look out for.
Of course if you use them for gaming occasionally, then Windows might make sense. Dual booting is also a possibility.
Oh, fair enough
. True. Could game on them or dual boot perhaps. Thanks for the suggestions.