If you get the Windows Media Creation tool, it will give you all the options. Personally I'd recommend just doing a fresh install of everything, as discouraging as that might be. I tried it the other way before, didn't turn out so well.
And there's almost no reason to not upgrade now, they added their information gathering to windows 7 and 8 in a recent update. So you have to turn it off regardless which version you're running.
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