OK, so maybe it won't help much with security (better to throw out a bucket with 1000 holes then try to patch it) but certainly a help w/ functionality, http://www.cygwin.com -A DLL to implement some of the *NIX API and a bunch of tools for developement, and there are tools to allow you to build makefiled sourcecode(I think). Lotsa stuff has been ported over to win32, not too shabby for a beginner looking to get used to emacs and whatnot, or someone forced to use windows at work.

-Greg