What are the primary folder and or files you want scanned on a regular basis (if necessary)? I have a lot of pictures from my digital camera in My Favorites, along with songs in one folder, flv videos in My Videos, etc. Most of these would not be worthy of a scan for computer time and resources. I also have other drives, and back up certain files to another hard drive in my computer. I keep Outlook Express on my “E:” drive which is also a separate hard drive. This is for any possibility of the main hard drive crashing and not being able to recover emails, etc.
It is easier to ask what folders and files shouldn’t I scan, rather than what should I scan.
The only area I 'don’t scan are my back-up drive images and my samples/tools that avast would detect as infected. Other than that I do a Standard scan ‘without’ archives once a week.
I don’t have large media folders (audio/video) and that may be something you could possibly exclude from ‘on-demand’ scans.