Dell dimension 3000

Hello,
i have a dell dimension 3000 it had xp on a friend try to put xp pro from a burn copy it in on my computer no but i cant get it go on the internet or get sound at all. this is my kids computer they use to do there home work. and other thing they need to do online. can any one help my fix this. ir have a copy that works. i look at ebay and they dont have any i called dell and they want what it would cost to buy it from a store. and at this time that just way to much money for me