Wireless troubleshooting

What do you do if your computer seems to want to connect to a wireless router that is not on your network, even after you have reconfigured the wireless settings on the computer and deleted the other wireless devices shown. I am trying to connect my computer to a two wire router and my computer says there is no internet access with this router and my neighbors linksys keeps showing up even after I delete it.
The computer operating system is a windows 7.