It would probably just be easier to get a wireless card / usb adapter for the PC than to try and figure out the networking nightmare that could become of your frankenrouters
The problem is everyone in my house has to own a PC, Xbox 360 (or PS3) and something that needs a wireless connection (iPhone, DS, PSP, ETC.). And no one wants to use a wireless connection for their PC because they tend to be crap. And no one wants to use a wireless connection on their consoles either because again, tends to be crap (and in the case of the Xbox 360s, very expensive).
I have to connect 2 PCs (must be wired), 3 Xbox 360s and a PS3 (again, must be wired, but one Xbox 360 is interchangeable with the PS3, since it is impossible to play both at once), a laptop (can be wireless), an iPhone, DS and PSP as well (all wireless) to a single modem.
This means I need a wireless router with 5 ports, but I have looked everywhere, and the maximum I have found is 4 ports.