This Microsoft Virtual Machine Converter (MVMC) tool can come in handy if you have a lab of VMWare images that you need to move to Microsoft Hyper-V: http://technet.microsoft.com/en-us/library/hh967435.aspx.
It supports converting VMDK (VMWare hard disks) created with VMWare vSphere 4.1 & 5.0 to Hyper-V file formats (VHD) for Windows Server 2008 R2 and 2008 R2 SP1.