The earliest version of Windows that the current versions of our plugins support is Windows 8. However, you can use earlier versions when we supported XP, Vista, and Win 7. Here is a link to the final versions before we dropped support for those OSs.
Mac OS X 10.6 and Windows Vista List
If you don't see a plugin you need in this list, it was released after we dropped support for XP, Vista, and Windows 7.