I personnaly dont have any issues wth Norton. Used it last year and was happy with it and would have used it this year but i got Kaspersky courtesy of our rep at work

. I have Webroot installed on the lappy which again was free courtesy of our rep and i wouldnt recomend Webroot unless i thought you were a d***k and wanted a laugh at your expense. Unless i get a better offer in October i will be staying with Kaspersky, i see a lot less machines infected with Kaspesky and it has a much smaller footprint than most of the others so not to impact on performance .
However i do believe most machines become infect through peoples own stupidity and dont put thier brain into gear before clicking on those lovely and tempting links.
As i say at work the problem is between the keyboard and the chair.