Ok first off a few months before i could play wifi normally but now
it has problems

Im using Linksys WRT54G by the way

While connecting it says error 5200
Check DHCP settings
Whats the DHCP settings

And can anyone give me a complete step by step guide to change the settings
( Last time i did it the routers settings were deleted )

You may ask your questions here, at the Nintendo Wifi Connection thread, instead of creating a new one.

And wiki is your friend. http://en.wikipedia.org/wiki/DHCP
The Dynamic Host Configuration Protocol (DHCP) is a protocol used by network computers to obtain unique IP addresses,and other parameters like: default router, subnet mask, and IP addresses for DNS servers from DHCP server. This protocol is used when computers (especially notebooks) are added to a network because these settings are necessary for the host to participiate in the network. This setting is periodically refreshed with typical intervals ranging from one hour to several months. This is determined on the server side.

Try this link:

http://www.nintendowifi.com/customersuppor...acturer=Linksys