I would suggest doing these things though I've never had an issue with Limewire or BitTorrent on a Mac. Before wiping the drive, do an "Archive and Install"- you should be up and running in a matter of 5-10 minutes. A and I is really quite quick, and leaves settings untouched for the most...
but who wants to wait 7 minutes. pop in the live cd from Apple (repair disk) and hold down the C button when you boot. Run diags and hope for the best. If bad comes to worse, run archive and install from system install disc. You'll be back up and running with all your info and quite a bit of...
Did you run the AirPort Setup Assistant in Utilities? No matter what, I can't get any AirPort basestation or Express. Just to clarify, your are asking about the basestation/express not the actual card in the PC?
DHCP is a standard. If it works on a PC, it works on a Mac, unix, linux, FreeBSD... There is not such thing as a router that is dependent on a PC running. Maybe older Macs wouldn't work with the router, but that's Apple's fault.
Check to see if you have fixed mappings set in your router...
Good idea... but if he can't boot, how can he select a different startup disk from Preferences?
First try the system repair disk. Second, hold down the option button during boot and you'll be able to select your startup disk. If you can't select your disk for one reason or another...