There are many free anti-virus and anti-malware programs out there. I would just like everyone to keep in mind that not all of them are legit. Make sure and do your research before installing any type of anti-malware applications.
Here are 3 tested and approved Anti_virus programs:
Avast - http://www.avast.com/eng/avast_4_home.html
AVG - http://free.grisoft.com/doc/5390/us/frt/0?prd=aff
AntiVir - http://www.free-av.com/
These are the anti-spyware applications I would recommend.
Spybot Search and Destroy - http://www.safer-networking.org/en/index.html
Adaware - http://www.download.com/Ad-Awa.....ag=lst-0-2
Spyware Blaster - http://www.javacoolsoftware.co.....aster.html
These are free applications. One anti-virus program may detect a threat while another will not ... this is the case with "commercial pay for" software also.
I only suggest these because in my years of experience the above mentioned work. If they do not ... then there are ways to go deeper into your system to get rid of the malicious software.
Make sure you download the latest updates for these programs regularly. Every week is what I would recommend. Also, the anti-spyware applications are not completely real time ... meaning you need to run them probably once a week as well. If you do not think you will remember to update them on a regular basis then create a scheduled task.
Finally ... Do NOT install and run 2 anti-virus programs simultaneously this will cause you more problems than solve. The programs will conflict with each other.
With the anti-spyware programs be sure you delete the archive files because Spybot will read Adaware's and vice versa.
**There is absolutely no fool proof program to protect you while online. Always use educated best judgment**