I recently reformatted and used XP pro. I use Linksys wireless card b. and wireless router b.
they are within 15 feet of each other and ive never had this problem before but evry few minutes it cuts out and i have tho choose the connection. I run excrypted but my friend with wireless across the street (being not so pc savey) doest use encryption. It picks up both coonections. I designated mine as the prefered and set the wep n evyrhting should be running.
I have a linksys wireless B USB adapter (Version 2.6) and had the same problem under windows XP... Odd thing was that under Windows 2000 it worked great. They've probably fixed these issues in newer versions of there wireless cards/adapters.