well each player needs thier own version of the game for a start i think, using one disc on a few pcs wont work...
but firstly man u gotta get both pcs connected via a lan network, wired or wireless, your choice. to test if u can see the other pc try going to network places and see if u can see the ither pc from there.
im just giving advice on what i did yesterday at my uncles work but im sure others here will be able to help yuo a lot more than i could. providing your intentions are legal.