Sysadmin Geek posted a guide about setup a VPN (PPTP) Server on Debian Linux

VPN-ing into your server will allow you to connect to every possible service running on it, as if you were sitting next to it on the same network, without individually forwarding every port combination for every service you would like to access remotely.
Using a VPN connection also has the upshot of, if desired, granting access to other computers on the network as if you where in it locally from anywhere across the internet.

While not the most secure of the VPN solutions out there, PPTP is by far the simplest to install, configure and connect to from any modern system and from windows specifically as the client is a part of the OS since the XP days and you don't need to mess with certificates (like with L2TP+IPsec or SSL VPNs) on both sides of the connection.

  How to Setup a VPN (PPTP) Server on Debian Linux