Here's the deal. USB 1.1 = 12 mbit/s USB 2.0 = 480 mbits/s 802.11B = MAX 11 mbit/s (realistically, ~6 mbit/s) 802.11G = MAX 54 mbit/s (realistically, ~23 mbit/s) Internet connection with...
I just found this article on the whole deal. http://www.everythingusb.com/forums/showthread.php?s=cae738e54f5ba5685d20accaa029a254&threadid=2596
So which is more practical? I have 4 usb slots, and 1 taken. I have room for a PCI card. My dad's computer...well, let's just say that might be a different deal. I'm going to get him a 802.11B ...
Summary: PCI for you, PCI for your Dad (unless he has no slots left). Of course: directly wiring at least one computer into the router is the BEST solution.
that's a good idea.
then you'd only notice the slower wifi speeds when transferring files across the network between PCs.