try this:

1. click on the start button

2. click on run, and type in cmd (that'll launch the command prompt)

3. type in "ipconfig/all" --> It'll tell you a whole bunch of stuff

4. the "default gateway" is the ip address for you router

5. if you need more than that, type in your routers ip address (or the default gateway that you got from the command prompt) into your internet browser...and that will give you everything you will ever need to know

so hopefully that helps you out