Part 1 : About the full license all in one Anti Virus software.
First of all, I must tell you that you NEED at least ONE full license Anti virus software installed in your main hard drive where you keep your Windows OS. Free Version will not help entirely.
Currently, I have the below all in one Antivirus software. It is preferable to get the one that has the firewall as well. Window's firewall is virtually useless.
I need some help here to put more kinds of softwares such as AVG and Avast. I haven't personally bought the full license out of them so I really can't tell.
But I will list Avira here to start off anyways.
Avira Antivir Premium Security Suite
Avira has an ability to find Viruses very well.
Avira is relatively cheap compared to other Antivirus softwares.
Avira's firewall is acceptable under normal operation.
Avira's Webguard is acceptable. It can block dangerous webpages.
Avira's do not use system resources much.
Avira can not remove the severe viruses most of the time even it detects them.
Avira is weak on finding Spywares.
Avira's webguard slows down the internet unless you set it to ''Low''
Avira forgets the ''Application Rules'' when certain amount of time pass.
Avira can get hacked but it is rare.
Avira is not that bad. I use this software to detect rootkits mainly, firewall and for Webguard. It does do some jobs. The only concern is that it can not remove the viruses most of the time as I have stated above but when that happenes, I use other softwares to delete it. Basically, You must use Avira WITH the free anti malware softwares and it does it's job nicely. Best of all, it doesn't use much system resourses and runs silently.
(I will update here if necessary. I really need more informations on other softwares from the users. Please email me with pros and cons and the name of the software you are using. Thank you)
NOTE on XP users:
Full licensed all in one Anti Virus Softwares will quit the support for XP with in next 3 or 4 years forcing all people to move to Vista and Windows 7.