Not Free:
http://www.3d-screensaver-downloads.com/christmas-screensaver.php

Free:
http://www.cool-screensavers.com/3dxmas.html
http://lan.freeze.com/LPQueue/856/index.asp?SessionId=1c10dac6-4e51-4580-b915-8e92094115bc&nat=0&cc=ca&cid=3484&lgid=570&a=4141&f=jsfeed

For desktops…..

Free:
http://images.google.ca/images?q=christmas+desktops&ie=UTF-8&oe=utf-8&rls=org.mozilla:en-US:official&client=firefox&um=1&sa=X&oi=image_result_group&resnum=1&ct=title
http://desktops.org.ua/category.php?pagenum=0&catid=27
http://www.yourwallpaper.com/holiday/christmas/

I hope this helps! Good luck with decorating your computer (LOL) for Christmas!

http://www.tnpsc.com/christmas/animated.html

http://www.kate.net/holidays/christmas/screensavers.html

http://www.frostythesnowman.ws/

http://www.freechristmassavers.com/

http://www.screene.com/free-screensavers/holidays-screensavers/christmas/showall.php

http://www.xmasdownloads.com/