For this, you have to install the Hyper-V Manager for Vista SP1 first . Then you have to tell Hyper-V monitor where VMConnect.exe is located. Usually, it is under C:\Programs\Hyper-V. Note that only a double click on a virtual machine will establish a connection. I first tried it with a single click because the mouse pointer changes to a finger when you move over the VM.
It also seems to me that the tool is a bit buggy. I got a couple of script errors while configuring it. But once everything was configured it worked flawlessly.
Download Hyper-V Monitor Gadget from here