I want to change the friendly name of my USB Wireless Lan adapter. (LevelOne WNC-0301USB). In network connections, on Lan or High Speed Internet section, the device has the name RT73 USB Wireless LAN Card #2, i want to remove #2 string from the name. How sould I do that?

You should be able to log in directly to your router via a browser. Once inside, you can change the name of the device, along with the network's name, administrator password (which you should do) and change the wireless networking security to be secured (this will keep outsiders off your network).