Norton Antivirus.

[Square Ball]

Been using AVG for a long time and never ever had a problem with it, i use it and Zone Alarm, and well to be on the safe side would run Adaware as well for the spyware stuff (they have stopped updating it)

[Donagh]

Keeps running itself everytime i log on at home, takes up to an hour to start up! 

Then change your scheduling. It's a machine not people. Has to be told what to do.