Powershell runtime
While the Windows Powershell 2.0 Engine feature is on by default in Windows 8, you need to turn on .Net 3.5 to actually use it, as mentioned here:
On Windows 8, the Windows PowerShell 2.0 Engine feature is turned onby default. However, to use it, you need to turn on the option forMicrosoft .NET Framework 3.5, which it requires.
Follow the steps in the above link to get it working.
While PowerShell 3.0 on Windows 8 is installed by default, PowerShell 2.0 isn't. You can go into Programs and Features and select "Turn Windows Features On or Off" and from there you can select Windows PowerShell 2.0 for installation.