Should questions about a specific version of something have both the general tag of it and the version tag, or just the version tag? For example: If I'm asking "How do the Home and Professional versions of Windows XP differ?", do I tag it [windows]+[windows-xp], or just [windows-xp]?

What about regular questions about Windows, i.e. If I have a certain version of Windows, but my question isn't specifically about that version, for example: "I need sound editing software for Windows. I'm on Windows XP.". On Mac OSX: "I can't get printing working. I'm on OSX." Do I tag it [mac] and [osx], or just [osx]?