While I don't have time for a full post, I just wanted to remind anyone visiting today that I only recommend Microsoft Security Essentials for older computers running XP and Vista computers with less than 2GB RAM. I recommend a combination of Avast! & MalwareBytes installed together, with each set to ignore each others processes, and either pay for MalwareBytes to get the automatic scans, or use my scripts to have it run weekly.
~Matt