Webroot System Eraser

I really need to get my system back to factory status; however, when I bought my Alienware computer, I was not sent all of the disks needed (particularly the AlienRespawn v 1.0 and 2.0 disks), so all I have is the system recovery disk. I've used it a couple of times, and now have multiple profiles that I don't know how to get rid of, and my system is slowing down a great deal. It doesn't even erase my hard drive, which I what I want, so whenever I go to the new profile, I have all of these files with programs that aren't on my Add/Remove list.

So, I made a boot disk using Webroot's Windows Washer; the problem? My mother has told me vehemently NO, that if I use it, my computer won't be able to recognize the system recovery disk without doing all sorts of... strange, voodoo things to the system. :\ My question is; is she correct about this? Can I safely use the boot disk?