It shouldn't be installed/enabled by default, but in case that it is, go to the Add or Remove Programs section in your Control Panel. Click on the Add/Remove Components button and then uncheck the Fax services item and click Next and follow the instructions. Otherwise, I'm not sure what you are talking about. I hope that helps.
More info here: http://www.microsoft.com/windowsxp/using/s...2october21.mspx