go into Start menu,
click "run",
type:
cmd
hit enter
type the following into the command prompt box that opens:
ipconfig /all
(please be careful of the space between ipconfig and / )
You should then get a screen with a lot of info on it. In that info will be your IP address and your default gateway (often your router).
You can do this on yours and your sons' PC or you could go into your router config page and get the information there
