Recovery from Rootkit virus

As a result of using AOL's special version of McAfee to detect and remove a Rootkit virus, my Dell B130 laptop (XP Pro, Service Pack 3),no longer connects to the Internet (neither by Connexant mode nor through BroadCom NIC), nor can it see the data on the LaCie hard drive that holds my backup files.   Running Recovery Console/ chkdsk /f  from the Service Pack 2 Installation/Recovery CD did not help, nor did reinstalling the drivers from the utilities disk.

A coworker told me yesterday that the same thing happened to his Dell computer at home, with AOL/McAfee knocking out his Internet.

I believe that a Service Pack 3 Reinstallation/Recovery CD might help, along with drivers for the modem and NIC.  As the old Mac laptop I am borrowing makes it difficult to navigate this support site, I'm hoping that someone will see this post and offer possible solutions or advice.  Thanks in advance!