Wii Ports öffnen

http://www.nintendo.com/consumer/systems/wii/en_na/onlineFirewall.jsp

Allowing TCP and UDP Traffic: The Wii console may require unrestricted access to several sites across various ports and protocols to function correctly. These addresses and ports vary, and may change in the future without notice. Many software firewalls restrict outbound access. Only if your firewall blocks outbound traffic do you need to enable this traffic:

  TCP:
  Allow traffic to all destinations on ports: 28910, 29900, 29901, 29920, 80, and 443

  UDP:
  Allow all traffic to all destinations. (Necessary for peer-to-peer connections and game play). Our Network Test tool can be used from a computer behind your firewall to test if outbound UDP is allowed.

Würde an Deiner Stelle mal schauen, ob Du die Console in die DMZ deines Routers packen kannst. Dann gehen sämtliche auf den Router treffende Verbindungen direkt zur WII.