PS3 and router.HELP!!!!!?

I purchased a router (Cisco Linksys) and was unable to install it because it said I needed to update to a Windows service pack of some sort. I tried doing this but it still didnt work. I was walked through with a Cisco CSR but it still didnt work. He told me that I would have to call Microsoft to update my computer and it could cost as much as $200. This is ridiculous! I just want to be able to play my PS3 online. Is this common for all routers? I paid $60 for this router and will return it. Does anyone have any recommendations? I am not computer savy at all.....HELP!