You are entitled to a refund for the OS if you are not using it. Be warned though- it takes ages to get your money back. When I switched over to linux a few years ago I had to wait over six months to get a refund for XP that came pre-installed. You should first go to the retailer and then if that fails contact Microsoft. There is addition information here (applying to North America- couldn't find the European version):
http://www.microsoft.com/mscorp/prod...nd/refund.mspx
LG