cygwin runs under windows (all flavors). For the most part, you don't even need to install cygwin if all you really want are cygwin compiled executables (ie perl, apache, etc), but you do need cygwin1.dll somwhere in your path.

I am a great fan of cygwin. But if all you really want to do is install apache and perl, then just go to www.apache.org and www.activestate.com and download the windows self-extracting executables.