Free Utilities

Anti-Virus:

Avast: http://www.avast.com/eng/download-avast-home.html

AVG: http://free.grisoft.com/ww.download?prd=afe

Firewalls:

Zone Alarm: http://www.zonealarm.com/store/content/catalog/products/zonealarm_free_firewall.jsp

Comodo: http://www.personalfirewall.comodo.com/

Disk Defrag  programs:

Defraggler: http://www.defraggler.com/

IOBit: http://www.iobit.com/iobitsmartdefrag.html#