Have you got the router working with the network cable plugged directly into it? This would be the first thing i'd do.
Then once that done, plug in your wireless adaptor/card make sure the network cable is removed as well as having that plugged in as well as a wireless connection usually affects your connection.
Go to Control Panel, Network Connections, right-click on the wireless network, click properties, click on Internet Protocol (TCP/IP) and then select properties, you may need to manually input an IP address, and subnet mask (subnet mask will prob be 255.255.255.0)