I expect halogen lights emit some level of infrared light, I know fluorescent bulbs do. But I think it's really a matter of noise vs an encoded signal. Mind you infrared light blasts from the sun too. I would expect the wii infrared to be a complex short range message, filtered if needed, probably in multiple IR wavelengths (theres a whole range you know, and I can't imagine a halogen bulb saturating a room with huge volumes of all wavelengths of infrared light which would mean lots of heat on everything the light hit, which is hardly there if at all from just a foot away).
No light through the path of my dumb simple tv remote ever stopped it from working, I seriously doubt a 21st century nintendo controller will be susceptible to any type of bulb --other than one on the front of a super infrared wii disruptor, sony is building a giant one in mexico. We better call the enquirer!