I have a network of 2 computers and an Xbox 360 in my house, with other people coming over and plugging into it frequently. I want to use another spare computer I have as a storage server, with a couple high capacity USB hard drives plugged into it. How should I do this? What sort of operating system should I use, Windows or Linux? I have a budget of $0. One computer on the network is running on Win XP, and the other ones are on Vista.