FreeFileSync sounds like it backs up irreplaceable files, such as your data files, photos, music, etc.; but it likely doesn't do an
image backup of your computer. What that means in plain English is, if your hard drive crashes, you won't have a quick and easy way to get going again.
You need to have a way to reinstall Windows, and all of your software, in addition to protecting the irreplaceable files. There are a few ways to accomplish this:
- Do full-image backups of your computer on a regular basis.
- Have your Windows install disk, plus all of your software, plus all install keys for Windows and your software; plus, all of your irreplaceable data.
Obviously, a full-image backup makes it easier to recover in the event of a crash. But you have to have somewhere to keep these backups. And you have to hope that they are stored on reliable media. Therefore, you could keep regular backups on one drive, and the most recent backup in a second location, such as online or on a second backup drive.
If possible, have a way to reinstall a basic copy of Windows. Also, if possible have a way to do a factory restore of whatever came on the computer when it was new. All of these are options that will give you some way to get back up and running in the event of a disaster.