cvs for windows

The WinCVS GUI:
http://www.wincvs.org/
for some features needs python:
http://www.python.org/
maybe you would consider using:
http://www.lucatec.de/tools/proxydiff-en.shtml
to select the diff tool used for wincvs.
or CVS SCC Proxy - add plugins for VS, BC++:
http://www.pushok.com/soft_cvs_proxy.php

Tortoise CVS - a windows explorer extension:
http://www.tortoisecvs.org/

CvsIn - an extension for Visual Studio:
http://www.geocities.com/kaczoroj/CvsIn/