Utility Disk is not giving me the option to erase my MacBook '11 hard drive
I recently erased the Bootcamp partitioned drive on my MacBook '11 laptop (ver. 10.10.5 Yosemite) and when I went back to try & launch Mac OS Diagnostic, I was unable to get back to that utility at boot up (after many unsuccessful attempts via Command+R keys and Command+Option+Shift+R). When I go to Utility Disk to try and erase the hard drive from there, the option to Erase is not available.
Can someone provide guidance/insight on how I can wipe my MacBook hard drive some other way? Can I try from a another Mac computer and connect via Firewire?
MacBook