Change the Registered Owner and Organization in the registry - Windows XP

Click Start, Run and type regedit, and then click OK. Navigate to the following location:

HKEY_LOCAL_MACHINE \ SOFTWARE \ Microsoft \ Windows NT \ CurrentVersion

Backup the key by exporting to a file.
To change the registered organization, double-click RegisteredOrganization.
Under Value data, type the name that you want, and then click OK.
To change the name of the registered owner, double-click RegisteredOwner.
Under Value data, type the name that you want, and then click OK.
Click Exit on the File menu to quit regedit.