Hi,
in the Email/Outlook-provider settings you can choose "Silent Mode" and set it to MOVE found viruses automatically to the chest.
Then you shouldn't see the popups for the mail-viruses anymore.
You'd better check/clean the viruses from the chest then once in a while..
auto-
Deletion is imho not possible in Home Edition
you might want to read the avast docu/help and/or the FAQ's on avast homepage or here in the OffTopic-forum