I think i may have a solution
Well I was on chat a little earlier and asked the question
As it turns out , I can get XP Home Edition for £25
My local sells the COA and CD for £25 so it seems legal (and they have a microsoft certified engineer so i dont have any doubts in that department
)
As for the mobo im going to order it tomorow ... mabe my computer will be itself again after all...