Currently Being ModeratedDec 7, 2012 4:31 PM (in response to macerdepasco)
If you have Time Machine backup (up to date) this should do.
You will have to install new system and restore during setup.
You should be up and running as before the HD swap.
Currently Being ModeratedDec 7, 2012 8:49 PM (in response to macerdepasco)
Another way would be to create a bootable clone of your entire system. I did this for my hard drive replacement. After you create the clone on an external hard drive, boot into it and erase your internal hard drive - I would not turn over a hard drive with my personal info on it. In any case, when the iMac is returned, you can simply plug in the clone you created, boot into it and clone back your system. It'll be exactly as you had it previously.
Additionally, if you should have Applecare and are in the US and within 50 miles of an authorized service provider, you can request in home service. I did that - the tech came to my house and the whole process took about an hour and 20 minutes including the recloning.