Hi -midnight,
System restore was designed to pull a computer out of a major failure like a bad or corrupted driver installation, etc. A good deal of data on your computer can be lost each time you restore as not everything is backed up. It has been suggested to you before to use a drive imaging program as that will completely restore a previously saved copy of your hard drive. I believe you agreed to have a friend do this for you. You do not have to disable Avast's self defense module when restoring a disk image.