Upgrade Issue

have the MacBook Pro silver 2008 model and had upgraded it to Lion 10.8. As I had upgraded to a new iMac I gave the Laptop to my wife. I had transferred via Migration assistant from her Dell running Windows Vista. Unfortunately, I messed up the user accounts due to the way in which MiG Asst suggested I had two similar names, which then caused issues with filling my 250GB hard drive. In deleting User accts and other attempts to reclaim disk space, as I was faced with problems, I backed up to external drive. Then reformatted laptop and put back the Original operation OS X disks. Unfortunately I had overlooked these were V10.5.8!

I tried to use Migration Assistant via the external backup drive, but again worried about the warning about two similar User names. I understand that my latest Lion 10.8 is on the drive, but not confident how to recover it! 😕

Basically I want to put the Laptop back to its former state as a simple laptop for my 70 Yr old wife to understand and use with her iPad. All her original files etc are still on the Dell Vista Laptop.

Any help would be so appreciated...

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