Let me be blunt. I've always considered McAfee plus Windows ME to be a toxic combination. It was Windows ME where McAfee first "Waterloo'd" and continued to bomb for years.

My prescription which you can take if you want or not:

1. Be Parasite Free. I consider it non-negotiable to eject all pests detected with the five tools noted at:
http://reviews.cnet.com/5208-6132-0.html?forumID=32&threadID=1313&start=0
CWSHREDDER moved to http://www.spywareinfo.com/~merijn/cwschronicles.html

2. Eject (uninstall) McAfee and try a less resource hungry AV like Free AVG from http://www.grisoft.com

Bob