I periodically use Remote Desktop to access files and programs on my main pc from my laptop . This works perfectly when I am accessing it from my own home network, but not from anywhere else. How can I configure the router to allow Remote Desktop connections from outside the network and how can I make sure those connections are as secure as possible?

The PC that I am connecting to is running Vista Ultimate and I am using a relatively basic Netgear router, WGR614 if I remember correctly.