How to unregister Macbook from one apple-id and register to an other

I have an iphone and an ipad with my own apple-id. My son bought me a macbook but installed and registered it with his own apple-id, instead of with mine.

I want to unregister the macbook from my son's apple-id and registers it with my apple-id, so I can synchronize with icloud all my devices.

I did some investigation.

Till now evenhow I see two ways and I am not sure which one to choose.

1. On the Macbook I can go to supportprofile.apple.com. This is the My Support Profile of my son. I can remove the Macbook here. Now I can do the same on my ipad with my apple-id and add and register the Macbook as a new product.

2. On the Macbook I can go to Itunes>Store>Show account and remove the Macbook here. Now remove the authorization of my son in Itunes>Store>Remove authorization and then add the authorization of my apple-id.

The second way seems me a little more complete but I am not sure. I found the information here http://support.apple.com/kb/HT4627?viewlocale=nl_NL&locale=nl_NL and here http://support.apple.com/kb/HT1420?viewlocale=nl_NL

I am also not sure if I am complete with all the steps.

I hope anybody can inform and help me with this problem and maybe mention risks.

I have a dutch Macbook with Lion, so maybe the terms are not totaly equivalent to the English terms in the menu's.