This probably has been asked before, but I had no luck finding the answer I was looking for. I have a program that runs on my computer. Now I can share it with my network and they can play it, but is there anyway I can open a port on my router and use it to access the files. I hear hackers always use open ports to hack a computer. But how could I use an open port to access my own computer from school.

I just want to know if I can play a game I got on my laptop from another network.

VNC will do it:
http://www.realvnc.com/
It's quite an education to set it up, but it's used by a lot of people.