norton & other antivirus software
Nowadays, more than half people in the forum says freeware antivurus software is good.
Actually, one of my family member says that Avast is not good, lots of people says MSE is good, but he said the good antivirus software is Norton. This is my process using antivirus software: (the softwares are slowly improved)
Avast => AVG => Mcafee => Norton Antivirus => Norton 360
The N360 is the better antivirus than other but to use N360 first you must purchase the Norton 360 product key.
So, the answer for any software will be Norton 360. The answer for freeware only will be Microsoft Security Essentials.