From time to time you need VM to play and forget. It would be cool to have something like Vagrant, але маємо те, що маємо. So here few links when you can get preinstalled virtual machines with Windows.
One of the best sources of virtual machines up to date is Modern.IE site. Technically this VMs are intended to test Internet Explorer, but I hope you will be able to accept and live with this. Virtual Machines are packed for almost any virtualization platform such VirtualBox, VMWare and Hyper-V. You can find all desktop versions: Windows XP, Windows Vista, Windows 7 and of course Windows 8. All VMs are trial for 30 days and you can reset this 2 times, so 90 days of usage.
For Windows Server 2012 go to trial page and download Evaluation VHD. This is 180 days trial. Obviously works in Hyper-V but also works well with Virtual Box (ensure that you have last Virtual Box, there were bug with VHD based images).
Windows Server 2008 R2 trial VHD – could be downloaded here. Should also work in Virtual Box.