Swami; go to your ADMN console, on the Folders structure, select On-access scanning tasks, right click your Resident Task (could be the default, I don't know), select Properties, on the providers section look for Standard Shield, select Advanced, there will be the options you need, I'm going to paste the help text about this section, it could help you to decide what do you want to do, keep in mind that you could need to do this on the other providers.
"Silent" mode. It is useful mainly for server operating systems. This option ensures that the resident protection will not require any user interaction and will not display any windows. For this reason, it is not recommended to set "choose action" on the Virus page in silent mode, because the interactive action choice requires user interaction of course. It is better to preset some particular action, such as deleting the file or moving it to Chest.
With answer Yes (OK). All avast! questions that would be displayed on the screen under common circumstances, will be replied Yes. If the selected action is choose action after all, pressing the OK button will be simulated.
With answer No (Cancel). All avast! questions that would be displayed on the screen under common circumstances, will be replied No. If the selected action is choose action after all, pressing the Delete button will be simulated (i.e. the infected file will be deleted).