Transfer all content to another iMac?
I have an older iMac that I was using that I would like to give to my wife as a replacement for her even older iMac. I have used firewire disk mode and even Time Machine to set up a New iMac, but I have never attempted to set up an existing iMac with all new content from another iMac. I am sure I could just wipe my old iMac and reinstall the system software (so essentially a new iMac) and then just use set-up assistant to transfer everything from her Time Machine.
But is there maybe an easier way to just get all her files and system to transfer over and just replace (overwrite) my excisting files?
iMac, OS X Mountain Lion (10.8.2)