If you want the registry key to contain value X or Y. If that is the case, you should be able to do the following:
Where tblRegistry.Regkey Like '%SOFTWARE\Microsoft\Windows NT\CurrentVersion'
And (tblRegistry.Valuename = 'CurrentBuildNumber' Or tblRegistry.Valuename = 'ReleaseId') SubQuery1
On SubQuery1.AssetID = tblAssets.AssetID
For getting multiple values in one report, you will need a second subquery like:
Left Join (Select Top 1000000 tblRegistry.AssetID,
tblRegistry.Regkey,
tblRegistry.Valuename,
tblRegistry.Value,
tblRegistry.Lastchanged
From tblRegistry
Where
tblRegistry.Regkey Like
'%SOFTWARE\Microsoft\Windows NT\CurrentVersion' And
tblRegistry.Valuename = 'ReleaseId') SubQuery2 On SubQuery2.AssetID =
tblAssets.AssetID
FYI I moved this topic to report request as this is report related.