Well, I'm not entirely clear what you're trying to do, but I'll tell you what we're doing and you can see if it matches what you're interested in. We have a couple of different modes, but the configuration is pretty much the same.
Basically, we use openSUSE 12.1 (for now, probably move to 12.3, soon) with the Xen hypervisor. Xen packages are included in openSuSE, and several other Linux distros, and the tools are readily available available for managing it. We install the Xen packages and boot the system into the Xen hypervisor with the Linux kernel. We then complete the setup of a desktop environment in dom0 for some users, so that they log in and use the Linux-based system. The Linux-based dom0 is also added to our Oracle (Sun) Grid Engine cluster, and our Ceph storage cluster. This allows us to aggregate the CPU power and disk space of the local systems and distribute load across them.
From there we install a couple of VMs depending on the user. For some users, we install a Windows 7 VM and actually pass through graphics, USB, and sound to the Windows VM. This makes the Linux system look like a Windows system, and lets us control the amount of resources used on the Windows system and keep the rest for the Linux system. For other users we just set up a Windows VM and configure rdesktop connections to that Windows VM. The hypervisor can support many VMs - as many as the resources in the computer will allow - our deployment is pretty limited right now. We have roughly 80 hosts that we use in this fashion.
The thing that's kind of missing from our setup, and that we'd like to figure out how to do, soon, is some sort of centralized management console. There are several possibilities - XAPI (XCP), OpenStack, Convirture, CloudStack, DevStack, etc. openSuSE has some of the basic pieces built in - for example, libvirt - and there are some add-on repos with the packages you need to add the rest of it, but you have to piece the rest of it together, and that's proving to be a bit of a challenge.
Anyway, not sure if that's what you're looking for or not, but it sounded similar to what we're doing and what we're trying to do.