Hmm, I have several laptops running at home and one of them running Vista drops the connection once or twice a day, the others running XP never drop the connection If you reboot the computer and your connection comes back on then its unlikely to be the router, more likely a problem with the internal wireless card in the laptop. I kinda fixed mine by disabling the onboard WiFi card and and replaced it with a USB wireless stick which limited dropouts to once a week or so. There's also an option to turn off the WiFi card when the computer is idle, this is enabled by default and needs to be disabled as quite often the card is unable to wake up from its slumbers. Also, after some experimentation, I've found that setting static IP's for devices attached to the router improves stability a tad.
Just read your latest post and yeah, if you're having to reset your router constantly then it needs replacing. Mine often goes 6 months without a reset
Pete