virtualbox.org

In attempting to move a Guest from one WinXP Host to another WinXP Host, there is no way to keep the Guest settings. The .xml file contains links to the windows register. I thought the Idea behind using VirtualBox was the ability to move a guest. Such times would be to roll out a vm to client workstations, moving a VM when a host goes down and moving to a back-up machine or using it as a portable system between a home and work computers. The references to the windows registry makes this a chore to create the the .xml file and then have to register the drive for the OS. Can all references on the guest .xml file be made transportable?

There is no link to the Windows registry in the .xml files. If you are referring to the registration of the drive(s), then those are stored in the VirtualBox.xml file in the root of the VB settings folder (Documents and Settings\<username>\.VirtualBox).
You can transfer the full settings and VDI file if you unregister the VDI and other attached drives (like cdrom), then use the VBoxManage command to register the VM, then add the VDI to it. See the user manual for the reference and usage of the VBoxManage command.