It should work if u access what is in that screen shot through the Administrator (GOD) account.... (It is actually named administrator.....lol)
not your administrator account that you gave a name you always use.....
It is accessible, you just have to correctly open command prompt with admin rights and type the command with the yes in it....
As for a system repair install, I have lost data before with VISTA home premium when i have done that....
what happened was my user files were missing and my programs were still installed....
cuz my user was deleted.... I thnk i clicked the wrong option before though if you watch what is clicked you should be fine