check out this link:
http://www.epanorama.net/circuits/pa...l#relaycontrol
I have used the simple circuit design in the past with no damage to my motherboards. Since you only need one output, i suggest using a solid state relay. They use opto isolation so it can't hurt your motherboard. Not sure if your going to need resistor to keep it from pulling too much current from the port. If you are using XP or 2000 you will probably have to install a driver to access the parallel port from dos.
If you look elsewhere on that page theres info about controlling the port using a web interface. If a small webserver is run and you have wireless networking, you could easily build a remote starter. Just make sure you have security on the webpages.