You didn't tell enough but you did reveal you only have the issue with IE? Answer 1. Don't use IE.
Answer 2. Set the wifi card to not turn off. Try http://www.tomshardware.com/forum/21841-42-connection-drop-intel-wireless-3945-mini-card
""Allow the computer to turn off this device to save power""
This setting can be problematic. I.E. Does not work. If that fixes it, call the machine in and make your warranty claim.
Answer 3. The router has set the SSID to be hidden.
Sorry, that's the side effect of that. Next time follow the Cnet Networking forum sticky settings. Those are hard won knowledge and well worn.
I am using Windows XP and Explorer 7. When I am not using the internet for several minutes and then try to click on a website, a message appears saying I am now offline and to try again. I clicked on Tools and unchecked the Work Offline, and it reconnects. However this keeps happening. My wireless connection is stable with good signal strength. Is there any way I can stay connected as long as I wish? Thanks.