Notes about setting up Vista x64 as a guest virtual machine on my Windows Server 2008 x64 machine.
The installation ran relatively smoothly. I pointed the Hyper-V wizard at the Vista x64 iso and the installation happened.
The only tricky part was getting the network connection up and running. On Hyper-V, under settings for Vista x64 I had to add a Legacy Network Adapter and set that to my point to my Virtual Network. I also left the MAC address at Dynamic and unchecked the "Enable virtual Lan identification" check box.
When setting up Ubuntu Linux Desktop x64 I had to use the same strategy with setting a Legacy adapter to get it to hook onto the network.
I read somewhere that it's the x64 part of these operating systems that cause you to have to use the legacy adapter. I'm right on the edge of my knowledge at the moment as I've never done any of this before so take what you read with a pinch of salt. I now believe that it's because the Integration Components (IC's) are not available for these OS's.