✔ 最佳答案
It depends on you...
Internet security suite is always good ...
Here you can see the different between AVG AV and AVG IS....
http://www.grisoft.com/ww.download-trial
If you don't like to spend any money for an AV ... so.. you can download the AVG Free version and... you can use a free Firewall and a Anti-Spyware such as Comodo and Ad-aware 2008 free version or windows defender or SUPERAntiSpyware or something like that...
Gud luck...
:-)