Let's analyse the situation:

You wanna leave Windows for some reason:
* You wanna reduce costs for your business?
* You don't like MS's "anti-piracy" measures?
* You're just sick of the cycle of spending money on a new system when your existing one is fine?
* Maybe, just maybe, you do NOT want to be tied to Microsoft any longer?
* ("Insert your own reason")

Whatever it is, you may end up looking at Linux as a cost effective alternative.