you paid a hundred for the computer. That tells me that it maybe worth spending a like amount to do a new installation of windows XP Home or pro but i wouldn't try Vista....because Vista will not likely support any of the older hardware that is installed in an older computer system. You didn't say what operating system is installed...if it is xp and there is a sticker for the coa then all you need is the installation disc. call the manufaturer and see what they will charge you for a replacement restore disc.