These advanced automated options are only available in the Pro version.
You only have a limited option in the Home (free) version, to send the infected file to the virus Chest (silent mode, with general answer no, see below).
My own feeling on this is you should use the default interactive action (I appreciate you don't want to be disturbed but if this is such a regular occurrence you need to take other measures). This way you know exactly what is going on with your system. If you are getting so many warnings, that you want to automate this process, I believe you should review your security practice - filter emails at source, delete from server rather than download them, review the sites they visit, etc.
See the avast help file, Resident Protection: Internet Mail Provider Settings - "Advanced" Page.
Click on Internet Mail and then on Customize.
Go to Advanced tab and select Silent Mode and the General answer No.