click here direct link to pdf setup diagram
From what i can gather you want set both pc's up so they have independant internet access. You voyager modem only has provision for a usb connection, and your router only has ethernet.
The way i would get round this is to plug both pc's into the 4 port d-link router via ethernet cable. Then I'd fit a usb to ethernet converter inbetween the router and modem, you can pick them up from click here for as little as £13.04 delivered.