Free security
Be secure
WOT is a free program that will warn you before entering a dubious site.
It's another security layer, but it is not a replacement for anti virus.
Maybe you are not sure which program will suit your pc?
Remember that not two machines are identical; what works well on one may not be optimal on another.
Try more than one before you decide - but not all at the same time as they may conflict.
Free Anti Virus
- AVG: http://www.avg.com/product-avg-anti-virus-free-edition
- Avast: http://www.avast.com/eng/avast_4_home.html
- Aviras AntiVir: http://www.free-av.com/
Free Anti Spyware
Free Online Scanners
If you want a 'second opinion' try this: http://www.mywot.com/wiki/Online_tools
Free vs. paid
Please note that "Free of charge" usually means non-commercial & home use only
(and both of these conditions should be met). A paid version is still better, if you can afford it...