After a bit of testing I found the following queries work for filtering policy to different OS levels, and computer roles:
Select * from Win32_OperatingSystem Where Version like “6.1%” and ProductType = “1”
To further filter policies based on versions and roles the following properties can be used:
To filter the by OS version, change the Version property to:
Windows 7 or Server 2008 R2 = “6.1%”
Windows Vista or Server 2008 = “6.0%”
Windows XP = “5.2%”
Windows 2000 = “5.0%”
To filter by the different roles the computer might have, change the ProductType property to:
Client = “1”
Server running a Domain Controller role = “2”
Member server (server that’s not a DC) = “3”
The % character in the above queries is a wildcard for any characters that follow, so you could therefore use Version Like "6%"to filter for OS's which are Vista and later.
To apply the filters, you use the Group Policy Management Console (GPMC). In the WMI Filters section in the right hand pane, click right-click and select New. Then give a name and description, click Add then enter the filter into the Query box. Then click Ok and Save.
To apply the filter to a policy, select the policy in the right hand pane, then on the Scope tab under WMI Filtering select your filter.
There are a few limitations, like you can only apply one filter per Policy (but you can have more than one query per filter) and the Queries are a property of the policy not the link, but overall they’re a very powerful tool.