To configure your network to obtain a fixed IP address:
Go to Start/Settings/Network and Dial-up Connections, right click Local Area Connection, choose Properties/Internet Protocol (TCP/IP) then Properties again, check the tick box for "Obtain an IP Address Automatically"
This will then automatically take the DHCP settings of your ISP.
Also make sure the firewall is disabled before you try to connect. Once everything is connected enable the firewall.