If you need to do some basic server virtualization scenarios then Hyper-V server will be the perfect fit for you. This version of Hyper-V will be delivered as a free download very soon. I’ve added the table which outlines the differences between the different versions of Windows Server 2008 with Hyper-V and the Hyper-V Server 2008.
The following table outlines which Hyper-V–enabled product would suit your needs:
Read more about this Hyper-V server here: http://www.microsoft.com/servers/hyper-v-server/default.mspx