You need Samba. Its a software package for Unix/Linux that allows file system sharing between Unix/Linux and Windows among other things, including allowing Unix/Linux to be a PDC or just part of a windows domain. I could go on for pages here on how to configure this. If you installed every package when you installed Linux Samba is already installed, you just have to configure it. If you don't have it you can get an rpm. Also, look at swat (web based management for Samba - good if you're new to Samba, but you don't need it as you can always edit smb.conf). For docs on Samba go to
www.samba.org.