I guess the difference being I don't have any scheduled scans, but that doesn't really make difference to what I have said, since it is a configuration file it will reach its level once you stop tweaking settings or adding scan tasks.
David, it looks like you haven't really read what I said. The avast5.ini file is being added to each time an Explorer context menu scan is done, and when a screen saver scan is done, and what is being added is not configuration settings or alterations.
Look at the example I have posted, check the number of the highest Task shown in your file, do a simple single folder scan from the context menu, and then check your file again. I'll be surprised if it is not doing the same thing on your PC, because it is repeatable on 5 PC's we have we have looked at so far here, all XP, some SP2, some XP3.
I did say I was not concerned with the actual size of the file as such, it is just an indication of changes occurring well outside of what would be expected from a normal configuration file. i.e. to have increased from 8KB to 180KB in just a short period, however I do use the context scan a fair bit.