If you use Windows System Restore you may have suffered frustration when the system restore point cannot be restored by any reason.
If it is related to Avast (as antivirus can block some “changes” that occur within the restoration process), you should, first, disable Avast self-protection module in the “Troubleshooting” tab of Avast settings.
But most of the issues could be bypassed using restoration at Safe Mode.
“Restore Point Creator” could do it with few clicks.
Why don’t you take a look? http://www.toms-world.org/blog/restore_point_creator
Also it can manage old restore points, automatically create restore points (i.e., schedule the creation), manage the available space for restore points storage, etc.
Side by side with full system backup (yeah, the safer option, and you can take a look in the free Macrium Reflect for it: http://www.macrium.com/reflectfree.aspx), Windows System Restore could give you a fast and painless restoration (even faster than full system restoration).