Hi Lynn,
In regards to your Atheros drivers, here's the direct link to what you want - Drivers for Atheros AR8152 and Windows 7
Once you get to that page, click 'click for download', and after a few seconds, a download prompt will popup.
Have you tried changing the boot priority to make the optical drive #1? If so, check all physical connections to the optical drive itself.
Since this is still an analysis in progress, I would hold off on 3rd party antivirus software until we are sure your original issues are all solved. In the meantime, install Microsoft Security Essentials for an antivirus - Microsoft Security Essentials - Microsoft Windows
Regards,
Patrick
