Raise the router above furniture level, relocate cordless phone, video sender etc away from computer or router.
Try changing channels -- the different frequencies they represent work better or worse in different environments. If you detect neighbouring wifi, move to a channel at least 5 stops away.
WE HAVE A IN HOME WIRELESS NETWORK USING A D-LINK DI-624 ROUTER (wireless G). THE SIGNAL INTO OUR GAME ROOM IS TOO LOW TO RUN OUR XBOX360 LIVE. IN THAT ROOM, WE HAVE ENOUGH OF A SIGNAL TO MAKE THE INTERNET CONNECTION BUT THE SIGNAL IS JUST TOO LOW TO RUN THE GAMES. WHEN WE MOVE THE XBOX UP INTO THE SAME ROOM AS THE ROUTER, THERE'S NO PROBLEM. MY FIRST OPTION IS NOT TO UPGRADE THE ROUTER AND HAVE TO REINSTALL NEW WIRELESS CARDS IN MY 3 CONNECTED COMPUTERS. HOWEVER, I'VE READ SEVERAL POOR REVIEWS OF SIGNAL BOOSTERS. ANY SUGGESTIONS? THANKS