I'd say your first step is to determine why there is a user called "qcsuser" on your Mac. This is not normal. "QCS" can stand for "Quality Complaint Settlement", so do you have any software on your Mac to which that description could apply?
Have you owned this Mac from new or did you buy it from someone else? Possibly it's a hangover from software that was previously installed.
Anyway, you ought to be able to use finder to browse that directory to see what it contains. If you are not authorised to it you may need to use the command "sudo ls" in terminal to browse the directory.
I can only suppose that it originally had some sort of quality assurance sotware on it that required sharing for some reason. If there is nothing in the folders I would be inclined to drag the whole qcsuser directory to the trash can and see if it breaks anything. If there are no obvious ill-effects then you could move it to an external disk or write it to a CD (just in case). If you use Time Machine then you could just delete it as you already have a backup.
That directory is not part of a normal OS X install so I wouldn't envisage any problems.