will 802.11g wireless pci adapter replace bad modem in a remote desktop?

It depends on what you mean by remote. If you mean over the telephone lines, that can't be done without adding a lot of technology anyway.

It would be best to connect the 2nd PC to the Internet and then to the router an then to the first PC. This is not for the technically challenged.

If you mean up to 30 metres from the router then you can use an 802.11g wireless adapter to connect a PC to it.

T
July 2009