^^That's the 802.11g PCI nic. Compusa:$60
^^That's the 802.11g USB nic. Compusa:$53
Either one will work. The USB adapter may give a little more flexibility in that you can use it in any computer with a USB port...whilet the PCI card will only work in...mid towers with PCI slots. And USB is hotswappable (PCI, technically, is too...but it ain't recommended).
Anyway...hope this helps. Do some shopping for the best price. Either one will work.