Win 7. Disable Internet but keep network?

I recently had my Internet disconnected, and decided to share my iPhone's Internet connection (tether) with my PC. Now, the iPhone connection works, but for some reason my PC prefers to use my original Internet connection thus no connection. The only way I can access the Internet is by going into adapter settings and disabling my router, but I do not want to do this as I have other computers on the network and I often share files.

So what can I do? I want to keep my router enabled, but don't want my PC to use it to access the Internet.

You MUST remove the ISP setting from your computer and set your computer to use your iPhone.

If the modem is separate from the router then either remove it or turn it off.