If you require all the devices connected though WiFi as well as the Ethernet ports of the Wireless Router to share the internet connection on your Windows 7 PC, you should connect the Ethernet port of the Windows 7 PC to the Internet Port on the Wireless Router. In this case, the Ethernet cable should be a crossover cable. Please make sure that the appropriate TCP/IP settings are configured such that the Ethernet port of the Windows 7 PC and the Internet Port of the router are on the same IP subnet. Check that these ports can ping each other.
If a connection is established, all the systems/devices connected through the other two interfaces of the Wireless Router ( Ethernet ports and Wifi) will be able to connect to the Internet through the Windows 7 PC.