Winders

I use Microsoft Security Essentials (free download) on my Win 7 machines and Windows 8 includes Windows Defender. There are other free AV packages out there as well, such as Avast.

I haven't used a paid AV on any of my Windows computers since XP was new. Of course the best defense against getting a virus in the first place, is using a little common sense to know what to click on or not click on and knowing what not to download.

Of the paid AV packages, about the last one I would choose would be Norton.

Vista?

Ouch baby...Vista was probably the largest mistake MicroSoft ever came up with.
Windows 7 in any version is fine.
XP Pro 64 bit worked very well I had a tough time moving to W7, yet I really like it now.
You could always go Mac OS, but that will cost you dearly.
Then you can go Linux on a PC with a slight learning curve.
Linux is kind of fun to fool around with in the different distros.
There's Ubuntu, Mint...Zorin etc...

Have fun picking one :)

To get your question answered you would probably have better luck on a computer oriented website.

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