till very recently I have been using Computer Associates e Trust Anti-virus programme, but the updates have gradually been more and more painful to download, using cable, even failing. After contacting CA they said to disable or remove Adaware, which I did and made no difference what so ever.
Outcome reloaded Adaware and changed to Grisoft AVG 6, the updates are normally in small packages, works a dream.
Please be aware, I have noticed Norton have a lower priced Anti-virus package, which when you load it turns out to be a 90 day version and have to pay out for further updates.