Turns out it was nothing to do with the security and more do to with the way my pc was originally configured to my modem and subsequently my router. My PC was configured to the wireless router using the IP from the modem i.e 82.<>.<>.<> when in fact it should have been 192.<>.<>.<>: the router.
Hence my Wii could not connect wireless since my laptop was already connected i.e two devices trying to use the modem's IP address at the same time.
Changed the configuration settings to allow for different devices to connect through the wireless router. If anyone else is experiencing similar problems, my router is a linksys WRT54GS - best calling the manufacturer directly.