It is of more use for people who look after someone's computer, like if you were looking after your son, daughter, parents computer, etc. You could set it up so you were notified if their system detected a virus.
Other than that it is of limited use and me I have never managed to get it to work on my system on dial-up. I only attempted to set it up just in case someone asked for help with it.
It is best to leave the avast settings at their default settings until you get to know the program a little better.