I have a 13 inch MacBook Pro (10.5.8 OS X - I think it's called Leopard). I do NOT have the installation CD - so I cannot reinstall the OS and thus ensure that I have securely deleted everything from my hard drive. By looking at the o/p from the System Profiler utility, I'm pretty sure my hard drive is NOT a SSD, although I cannot confirm this.
The reason I can't directly use the "Erase data" option under Disk Utility is because the 'Security Options' (as well as the volume format) button is greyed out. Volume format currently reads 'Mac OS Extended (Journaled)
I'm planning to securely delete ALL data on my mac using the following steps:
1) Using Disk Utility, I click the button titled "Erase Free Space" using a one pass method (or if I have time 7 pass method)
2) Once the above operation is complete, I plan to use 'secure rm' or 'srm' to remove all files and applications on my macbook.
3) Once step 2 is complete, I re-run "Erase Free Space" using whatever method I used in step 1 above (in order to remain consistent)
Once step 3 is complete, I assume that my macbook has been formatted and all data securely deleted. Could you kindly confirm whether this assumption is true or not? If not could you please point out steps I need to add to my existing process?