Right click My Network, and select Properties.
On the next screen, it should show network devices - you need to make sure that the one that is for your wireless is enabled.
Right click the wireless network device, and select View Available Wireless networks.
Then, when the list comes up, try to connect to any of the networks that are available.
Look for the ones named dlink, linksys, or netgear, that signifies that the owners have not changed the router from default, which usually has a better chance of being open (no security to keep you out)