As Russ notes, the so called backup in versions prior to FTM 2008 were dangerous as they merely made and renamed a copy of the file.
If there was a problem with the main file then you got it in the backup as well.
Careful genealogists back up their files to removable media and don't keep the copy in the same place as their computer.
Windows in Control Panel>Automatic Updates has a scheduler to allow auto back ups of any program.
Have you considered that option?