After a lot of poring through the MS website I discovered indeed, the upgrade DVD you are supplied with by default will be non bootable. But you can get a bootable one on application to MS.
The more tricky thing is to work out what licensing key to use with the volume license. Vista requires that every PC is activated, including those on a volume license. To make life simpler for network administrators the Key Management Server was invented. Every PC on your network installed off the volume license files will automatically try to find a KMS first. The catch is that you have to have at least 25 PCs on your network looking for this KMS before it will accept activation requests.
So if you are like us and only have a few PCs that are running Vista at this stage then you have to get a MAK (Multiple Activation Key) onto each one of those PCs. Perhaps rashly I went ahead and installed Vista on a couple of PCs as soon as we got the DVD, assuming we would be able to get the keys within 30 days. That time is almost up, and the MS website that we registered with still isn’t working properly. The MOE helpdesk (Datacom Services, also the LAR for Microsoft NZ Schools Agreement) has got us a KMS key so far, but all that does is activate our KMS server. It’s totally useless in our situation.