Do you know what is the best antivirus software that is available for free to download on the intern

You can go to http://www.download.com and read about the different AV solutions there. They offer everything including Paid, Shareware and Free software of all kinds for many OSes.

Here is just ONE site that offers some comparisons:

http://www.av-comparatives.org/

I just 'googled' the term: Comparisons Free Anti-virus

and came up with this list:

http://www.google.com/search?sourceid=na...

Personally, I used AVG until a couple of years ago when it became bloated and a PITA to use in addition to it allowing all kinds of infections onto my computer.

Now I use Avast and am THRILLED with it!!!

Check it out here:

http://www.avast.com/eng/avast_4_home.ht...

So that I'm not relying on only ONE database for protection, I back up my Avast with this On-line Scanner:

http://support.f-secure.com/enu/home/ols...

In addition to good AV, you also need protection from other types of malware like spyware and adware, etc.

Some free solutions for this are:

CCleaner

http://www.ccleaner.com/

Spybot Search %26 Destroy

http://www.safer-networking.org/en/downl...

Ad-Aware se Personal

which is a GREAT companion to SS%26D...again not relying on only ONE database! ;)

http://www.download3k.com/Install-Lavaso...

A good and _safe_ Registry Cleaner is TweakNow RegCleaner

http://www.tweaknow.com/RegCleaner.html