You'll need to settle those questions for yourself. But regardless of what you're trying to measure, the best way to get that answer is to use wget. wget is an excellent website "mirroring" tool that can download an entire site to your hard drive... and then you can simply peek at the folder's properties on the Windows desktop (or Linux, or MacOS X...) to find out how many files it contains and how much disk space they occupy.
For complete information about using wget, see the article How do I mirror another website?
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