After I start up my laptop, it will connect to the router (show the wireless symbol in the taskbar), but periodically I won't have an internet connection. If I turn my firewall off, my internet will work. Same thing happens, though, when my firewall is off already. I start my firewall, and I can connect to the internet.
The router is a Dlink WBR-1310 Wireless G Router.
http://www.dlink.com/products/?pid=474 and using Windows XP on a HP Pavillion ze4900 and fairly sure all drivers and such are up to date.