Want to move a VM from server A to server B along with its associated storage and snapshots in R2? Snapshots are associated with the VMs and not the VHD files. You should explore import/export. Soumya’s written a series of blogposts to get you started:

http://blogs.technet.com/virtualization/archive/2009/05/20/hyper-v-r2-import-export-part-1-the-case-for-new-import-export-functionality.aspx

http://blogs.technet.com/virtualization/archive/2009/05/21/hyper-v-r2-import-export-part-2-the-new-import-export-apis.aspx

http://blogs.technet.com/virtualization/archive/2009/05/22/hyper-v-r2-import-export-part-3-the-ui.aspx

http://blogs.technet.com/virtualization/archive/2009/05/27/hyper-v-r2-import-export-part-4-export-code-sample.aspx

http://blogs.technet.com/virtualization/archive/2009/05/28/hyper-v-r2-import-export-part-5-import-code-sample.aspx

http://blogs.technet.com/virtualization/archive/2009/05/29/hyper-v-r2-import-export-part-6-so-what-happened-to-configuration-only-export.aspx

Ben blogged about V1 (also called R1 now by some folks…) import/export: 
http://blogs.msdn.com/virtual_pc_guy/archive/2008/08/26/hyper-v-export-import-part-1.aspx
http://blogs.msdn.com/virtual_pc_guy/archive/2008/08/27/hyper-v-export-import-part-2.aspx