I seem to be having an issue where my connection to the wireless router drops out.
I have windows XP.

Another computer on the same network running vista seems to work fine, although a couple times when my net has dropped out I notice it also has a bubble displaying a problem about the network, but it is automatically fixed.

I have tried the 'repair' option when you right-click the wireless network on the Network Connections screen. It just sits there saying it's disabling the wireless, but I waited like 10 minutes and it seems to be stuck on that step.

I've tried disconnecting and reconnecting the router, doesn't help

I've tried disconnecting and reconnecting the USB antenna in my computer, also doesn't help.

I have gone to a command window and typed "ipconfig /release" and I get this message:

Windows IP Configuration

No operation can be performed on Local Area Connection 5 while it has its media
disconnected.

I'm not sure what that means but it sounds like the antenna died.

The only thing that seems to work is rebooting the whole machine, which gives me some period of Internet access, but this eventually happens again. I will start timing the intervals, but I often don't notice the net has died until it's probably been off for a while.

Also the problem with shutting down is that doing 'shut down' brings up that "windows is shutting down" screen, but it never actually shuts down, again I've waited probably 20 minutes or so for this before just hitting the 'reset' button.

What else should I try or check for?

Looked in the event logs to see if there's anything in there about why it doesn't shut down? I know windows 98 SE had that shutdown issue and there was a patch for it but don't think I ever saw it during my years of using XP.

As for wireless, install inssider, don't connect to your AP (delete the stored profile if need be to stop it connecting) and just let it sit there doing a scan. See if there are dropouts or other routers interfering.

Is the other computer wired or wireless? I noticed something similar happening to me once, turned out my router was rebooting every so often because it was f***ed.

Thanks whoop, I've installed the program you suggested, it's pretty sweet I'll keep that.
However, after posting this I installed Avast and did a scan, found a virus, and this hasn't happened since.