i see u have the gateway bridge bug that pops up.
disconnect the gateway and reboot, also try reinstalling your wifi drivers
my dlink utility tells me my wifi card is at 54mbits while windows says its 108mbs, when i transfer files locally the dlink jumps upto 72 and 96 then 108.
I think your problem isnt a problem merely how windows and the vendors drivers differ and why most people always say use the vendors and disable windows wifi etc.
eitherway u dont really need that gateway