Agree with the above; note that if you want to access the scanner directly from a Windows program such as MS Word, using Alt I-P-S, that will not work. You have to import the images with SaneTwain, then import them into whatever program you want. The SANE advice above is only for the scanner part.
The printer part can be served up with samba, and will be recognized as a network printer by Windows. Make sure you are not using "Home Groups" or whatever Windows 7 calls them, use "Workgroups", which is the older Windows network sharing used by XP. There is extensive documentation for using samba everywhere, but I can post what I do if you want.