Many factors affect the performance of Windows Server 2008R2 running in a VM. If you're experiencing mouse lag or slow screen redraws, here's some things to check:
<ul>
	<li><strong>Use the correct video driver
</strong>A default VMware Tools installation does not select the optimal video driver. After the Tools install completes and the subsequent reboot, go to the Device Manager and have the Display Adapter check for updated drivers in the  <strong>C:\Program Files\Common Files\VMware\Drivers\wddm_video</strong> directory. It should update and the display adapter will now be labeled as a VMware SVGA 3D device.</li>
	<li><strong>Allocate sufficient video memory
</strong>With the VM powered off, edit its settings and select the <strong>Video card</strong> virtual device. On the right, ensure a minimum of 8MB of video RAM has been allocated. More video RAM can be useful is certain use cases, but be aware that tweaking this setting will affect the virtual machine memory overhead on the host. The Settings editor includes a Video Memory Calculator. As usual, when "right-sizing" your VMs, you'll want to find the sweet spot that lets your VMs perform well without wasting resources through over-allocation.</li>
	<li><strong>Upgrade VM hardware
</strong>The ESXi hypervisor emulates real server hardware for each virtual machine, including CPUs, motherboard, NICs, and SCSI drives. After major host updates, new virtual hardware is available to your guest VMs. It's just like shutting down a physical server and moving the hard drives over to a new server, but with perfect compatibility. VMware vSphere 5.0 introduces even more capabilities to your VMs, including support for up to 32 vCPUs and 1TB of memory. If your VMs have a virtual machine hardware upgrade available, you'll see <strong>Upgrade Virtual Hardware</strong> when you right-click on a powered-off VM. Note that this operation cannot be reversed without restoring from backup.</li>
</ul>
<div>All these actions can be performed on a virtual machine prior to converting it to a template. For existing VMs, the second and third checks can also be managed via <a href="http://www.vmware.com/go/powercli">PowerCLI</a>.</div>
<div>More information on the WDDM driver can be found in VMware KB article .</div>