System Service Question

[gibot]

What is the purpose of scanner service? is it actively scanning all files that are accessed? If I already had a anti-virus like avast do I still need to have scanner service running where it scanned internet connection and file as they are accessed? The other question I have is about the updating service. Since I get the free version, I do not have the capability of scheduling auto update. Do I still need this service to run at startup? I have tried to stop the service and uncheck "Active after reboot" but everytime I reboot my computer it always started by itself? Thanks for the help. is Internet explorer integration same as SD helper in spybot 1.62?

[gibot]

How do I stop the scanner service? I have gone to setting and stop the service and also uncheck the "Active after reboot" option. It is stopped after reboot but as soon as I open a file, it would start by itself. Is there a way to stop it because I have anti-virus and it seems like the scanner service is doing the same thing as anti-virus. Thanks for the help.