i have two different approaches to get a remote access to windows machines.
first, i setup a ssh-sever on the windows-machine and then connect over ssh to that machine with portforwarding.
then i connect with vnc over my localhost to that windows-machine.
second, i use a virtual-machine with a nested win-installation, start a vncviewer, and the win-clients connect over the single-click-way of ultra-vnc to my vncviewer.
have a look at their homepage
www.uvnc.comand you will find much information about this topic.
i wish you luck and fun, it works.