Change the name your computer is registered to
First open your registry by
Run|Regedit
Then browse to
HKEY_LOCAL_MACHINE/Software/Microsoft/WindowsNT/CurrentVersion
Just change the RegisteredOrganization & RegisteredOwner key.
To input a new data,just double-click and insert a new one.
Good Luck

Note that this works for Windows XP.For other versions,the path should be
HKEY_LOCAL_MACHINE/Software/Microsoft/Windows/CurrentVersion