Hi. I could not find any information on the "Stop VSS when defragmenting NTSF volume" setting in the online help files. Please explain what it does/ when it should be used. I read the post about free space going down, but that does not explain the function, only leaves one to presume.
If not suspended, Windows will increase VSS size during a regular defrag. You'll lose some free space, however you can always regain free space by removing one or more old Restore Points using CCleaner\ Tools\ System Restore. I regard the selection as a minor option.