Get your PC-based NAS box ready to share
If you plan to convert a PC for your NAS device, you must reconfigure it and define an area to store files in. It will need a keyboard, a mouse, and a display, which may not be practical to attach and use in a closet or other out-of-the-way location. Windows XP's Remote Desktop Connection lets you configure and administer the machine remotely, so you can skip the peripherals -- though the BIOS in some PCs requires that a keyboard be attached unless you change this setting manually. Remote Desktop Connection works with Windows 95 through 2000 as well; go to Microsoft's site for the free download.
If you installed your OS on a small partition and created one or more other partitions for data, XP lets you share files by simply right-clicking a drive icon, choosing Properties, Sharing, and checking Share this folder (the option on some systems is Share this folder on the network). (The context menu's 'Sharing and Security' option invokes an unrelated Windows utility.) Most routers use the default Windows group, named 'MSHome' or 'Workgroup'. If you have renamed yours, you must reset it: In XP right-click My Computer and select Properties; in Vista right-click Computer and click Remote settings. In both versions, select Computer Name, Change and enter the workgroup and computer names.