Wow, so much information to digest, in order to help. Seriously, tho, maybe some more information would help. Like, how many computers? How are you trying to connect to the Internet? How do you know you are not connecting? Can you describe your cabling setup? what does the output from the "ifconfig" command look like?
Let's start with those (don't want to overwhelm you or us at first), and see what else we might need to know, and/or try to help.