You should always have antivirus protection on your machine.
I have always had great results with both AVG and Avira products both offering great free products and more in depth paid for versions. The paid for version offers extra peace of mind and support for those who need it. Click below for more information on either product:
Herts Computer Services was set up by Iain Murray to supply straight forward IT support to everyone according to their needs; individuals, consultants working from home and small to medium sized businesses. 