I don't think that Creative adaptor will work for connecting your Wii. It is used to connect a computer to your linksys wireless router, not the Wii to the computer. For that you would need the Nintendo usb adaptor which works slightly differently.
To get your wii through the linksys depends on it's configuration. I'm assuming the name it's broadcasting is "linksys", which is basically a beacon for your neighbors that free internet is available on your dime, but I digress..
Nintendo recommends it to be running on channel 1 or 6, and you will most likely need to set up some sort of DMZ or port forwarding to allow the Wii to run it's checks. On mine I set up MAC address filtering and give out IPs based on the macs, and then point DMZ to the Wii's IP address. The easiest bet would be to get some help from a techie friend.