I got some ideas from the web about this.
RAS REG Hack: . Hack the registry so ras stays connected between users, ?? weird I thought ras was all about the Dial-Up but a few wireless users said it worked? it cannot hurt to try. http://support.microsoft.com/kb/158909
Fast User Switching The use of, or Not Fast user switching, the first thing I searched for. Fast user switching keeps the other users programs going on the computer, causes its own problems. Fast user switching seems to ME to be the best method to try and "keep things going" as that is what it does. On the other hand Stopping things, resetting , could reset it and get it going again without physical removal.
What Software? The use of or Not the built in wireless zero configuration , microsofts OWN wireless software, which runs as a service. Vrses using some software that might disconnect between users (because it is not a service). What software is being used for the wireless adapter device?
http://forums.techarena.in/networking-security/1371294.htm
I percieve that 2 of these items are like the usual combination lock :-) and you would have to have at least 2 of 3 in the correct configuration before you are done. testing different ways , might be needed.
So that covered web users attempts to keep it connected. I assume if you could somehow achieve keeping it connected you might not have the connection problem? If it would hardware reset fully you might not have the device problem.
Even with a device problem, you could potentially script the removal of the device, and achieve re-connection. If the attempts to keep it connected do not keep it connected, you still are pulling the card out??? after about 1000 disconnections whatever port the card is in might get damaged.
So, for the device problem, we have a few possibilities. Purposfully setting the device TO shut off power in it's device settings power managment. the Idea here being to encourage a reset , even at log-off/in. Or the opposite.
Then you can test disabling the device in Device manager, then re-enabling it, instead of pulling the device physically. If it is possible to disable it in the device manager, it would be possible to kick it out at log-off, and kick it back in a log-in, in software using scripts. That should get a reset, and a reset should get a re-connection.
Speaking of "device" it would not hurt to know all the "advanced" options that are available in the network devices properties/advanced, just in case something there is part of the combination lock :-) I doubt it, but it does not hurt to look.
I cant believe that multi-users would put up with this kind of thing, and XP used simple methods, so I think there is at least hope.
This post assumes things, because the text of the questioner could have 2 meanings. I assumed Switching users on a SINGLE XP computer, and not other computers involved also getting the routers wireless.