Well, I created the CD with no problem. The CD boots just fine, but I get an error message:
Microsoft Standalone System Sweeper cannot be started. Please contact support.
Error Code: 0x8004cc05
Should I proceed with the other steps or is something fundamentally wrong?
Well, I've followed steps 3-5 and the situation has improved significantly. I no longer seem to be blocked from the internet and the PC appears to operate just time. I downloaded the Comcast's Norton-Based security solution. It first downloads something call ConstantGuard, which appears to be some type of gatekeeper for your browser. You then use constant guard to download the security suite which includes the anti-virus protection. The download goes fine, but then the installer tells me it's encountered a problem and has to quit. I've tried several times and I can't get the security suite to install. I've got a help request out to Comcast, but if you have any suggestions, I'd love to hear them.
Regardless, I'd like to thank you for your help. This felt pretty hopeless, but you've been incredibly helpful and patient.