Change apple ID without deleting everything

Question

When I bought a new iMac for my wife at the apple store, it was set up using my apple ID.  I would like to change it to her apple ID without having to delete everything on it. 
The reason why is that in everything that she does, ichat ect it has all my info on it, including my picture.  Is there anyway to do this, without moving everything onto an external hardrive and using a start up disk to start over?
I have checked in the user account, icloud accounts ect and everything is under her apple ID, I guess the computer is just hard wired to mine.

Answer 1

That is not really possible. In order to accomplish that you need to erase her computer, repartition it, then install OS X. After that it can be "registered" to her Apple ID. You must remove the computer from your list of registered products so she can add it to hers.
For more help see What to do before selling or giving away your Mac. Think of your situation as being the same as someone planning to give away their Mac to someone else.
Install Mavericks, Lion/Mountain Lion Using Internet Recovery
Be sure you backup your files to an external drive or second internal drive because the following procedure will remove everything from the hard drive.
Boot to the Internet Recovery HD:
Restart the computer and after the chime press and hold down the COMMAND-OPTION- R keys until a globe appears on the screen. Wait patiently - 15-20 minutes - until the Recovery main menu appears.
Partition and Format the hard drive:
1. Select Disk Utility from the main menu and click on the Continue button.
2. After DU loads select your newly installed hard drive (this is the entry with the mfgr.'s ID and size) from the left side list. Click on the Partition tab in the DU main window.
3. Under the Volume Scheme heading set the number of partitions from the drop down menu to one. Click on the Options button, set the partition scheme to GUID then click on the OK button. Set the format type to Mac OS Extended (Journaled.) Click on the Partition button and wait until the process has completed. Quit DU and return to the main menu.
Reinstall Lion/Mountain Lion. Mavericks: Select Reinstall Lion/Mountain Lion, Mavericks and click on the Install button. Be sure to select the correct drive to use if you have more than one.
Note: You will need an active Internet connection. I suggest using Ethernet
            if possible because it is three times faster than wireless.
This should restore the version of OS X originally pre-installed on the computer.