No offense, but I'm greatly relieved to say that you are wrong. Copying files from the old computer as I type. *whew*
Course, I still haven't figured out what I need to do to make the old one work upstairs...
Unless there's a break in the Cat 5 cable, the computers should be able to communicate just like they are now.
Also, the 3Com Lan Modem I suggested would replace the hub you have currently.