I don't agree with the advice to skip the monthly Windows security updates.
On a clean system, they are practically riskless. A recent one interfered with Zonealarm firewall, shutting off Internet access, but that was quite an exception. And they are easy to undo, if need arises.

For the remainder of your question, please read through the recent Newsletter discussion about using wifi: http://forums.cnet.com/5208-10149_102-0.html?forumID=7&threadID=299358&messageID=2800701