solved the problem with my lag

turns out the wireless box that connects my modem to my computor ( all wired to me no wireless actually used) gives me lag spikes .

i take the wire out and use just the modem and this way i have perfect ping , but none of my family get to use it , So THE BIG QUESTION IS :)

how can i get constant ping , without taking wires out and taking away the internet ? ?

Virgin Broadband , Belkin Wireless Box ( peice of shit wireless box ) :)

Flame if u must :) but help would be needed