The Previous Versions feature of Windows looks fine. However I don't seem to have any control on creations of backups of files in particular (as opposed to backup everything). If you change a file three times in a day, you'll have to wait up to 24 hours to get it backed up, and only the latest version will be stored.
With VCSs you can do 'commits': you explicitly tell the system to save the previous version of the file, and then you overwrite the visible file. Isn't there a similar option included with the built-in backup system in Windows?
If not I'd just use a VCS or backup system but it would be nice to use something fully integrated.