Deleting "Program files" and "windows"

[V4NT0M]

I had windows installed on hard disk A now i'm using that in another PC so windows is booting from disk B, but I cannot delete the windows or program files folders from disk A. I do not have permission, anyone know how I can delete them?

 

[V4NT0M]

Tried both already, doesn't seem to work, I'm the owner but still don't have permission