<<< but when i use a WEP encryption pass phrase on the usb software and repeat the same codes on the web configuration software for the router, I loose connection and the internet. >>>
The WEP or WPA encryption key should be set up in the router first and this must be done by connecting to it by ethernet cable. If you try to do it "wirelessly", as soon as you save the settings, the wireless connection will crash.
Once set up in the router, delete any existing 'profile' in the PC's wireless settings and go through the procedure to "Connect" again. In other words, run the wireless adapter's software, scan for "Available Wireless Networks", find and highlight the one that matches your router's SSID (network name) and select the option to "Connect" to it. You should be prompted to enter any WEP or WPA encryption key and, once "Connected", the wireless adapter should get its IP address by DHCP from the router and you should have network and internet access.