Wireless Internet Dissconnecting after an hour

I have a D-Link Router and every hour or so (varies) i can't load or d/l anything, wireless icon says that everything is connected, so what i have been having to do is go and unplug my router then wait, connect, and then i have to hit refresh. Please any sugguestions, for some reason i think i have to alter my router under the 192.168.0.1 thing
Please someone help, this is really really getting annoying.

 

Forgot to mention some possible important information.

I have a desktop (Win 98) and a laptop (Win XP) i installed Network Magic on both of them. It was a free service for 30 days, i still got the same thing where i would have to reconnect the router, so i uninstalled it on both computers but the problem still occurs. With Network Magic it setup everything by itself, i mean i thought everything would be fine considering Network Magic came with my router.

Also tried to go into CMD.exe and type in
ipconfig /release then ipconfig /renew

When it would not connect to the network, so i would have to unplug and plug in the router. I really hope that you can give me some suggestions.

Thanks

Wojman