Microsoft Security Essentials does the trick, does it not?

After one several years of using System Mechanic from iolo Technologies, and coinciding with the fact that my subscription was up for renewal this past Halloween, I decided to drop the entire security suite and go for the free Microsoft Security Essentials proposition, with antimalware, antivirus and antispyware included. However, something funny happened on my way to getting back my system to its usual stable state and that included a blue screen (the first one in more than a year!) but not before having my system frozen three times... I have to add here that I had also installed ZoneAlarm free firewall, another good product that I used for many years in Windows XP and previous versions. ZoneAlarm shuts down the Windows Vista firewall and everytime I turned it back on, my machine froze or got the blue screen, as mentioned. I gave Microsoft Security Essentials the benefit of the doubt and uninstalled ZoneAlarm. Now I'm back to normal.