To wii connection issues:
1) Set Wii to Static IP.
2) Use OpenDNS for your DNS server.
Primary '220.127.116.11', Secondary '18.104.22.168'
3) Set MTU size to '0' which is auto. Many will say put it to 1500 but if set to auto it will start at 1500 and change depending on your line to improve data transfer.
4) Turn on DMZ within your router and put Wii IP address.
Optional will be to connect via ethernet for better connections. Still the Wii settings should still be what is above. For help please list your router and I'll show you what you have to enter. As for the DMZ portion I'll try my best to walk you through.