Most of that is geek-talk. If you're just looking for a simple blog, you don't need to concern yourself with those (except maybe tagging).
I still have some homework to do to learn about things like "JSON" and "tagging" and "microformats" but I am really starting to grasp the concepts.
If you're curious, here is a good article on JSON.
Think of it like categorization, but on a less rigid level. Usually, within CMSs categories are set ahead of time. If you have a blog related to cars, you might have categories that relate to each manufacturer (Toyota, GM, BMW, VW, etc...). Tagging is done at the time of posting to provide more subtle cues as to the content. Say you're writing an article on BMW engines. Some tags for this article might be engine or improvements. Then, your reader can sort all of your articles to pull out all of the ones tagged with engine. It provides more robust navigation and utility to your information.
Again, something that the normal user need not concern himself/herself with. If you're creating your own designs, then it might be worth looking into. Microformats are ways to use CSS classes to specify content that can then be used/read by various software. So, your content has a dual purpose. For example, say you have the following code on a Contact Us page:
You could "microformat-ize" this by adding some specific class identifiers like so:
<div>The Example Company</div>
Using plug-ins to your browser, your browser would then be able to parse this information and automatically add it to your address book, for example. You can do similar things with geocoding, tagging, calendar events, syndication feeds (rss, atom, etc...). This becomes especially useful for screen readers, for example, and boost overall accessibility.
<div class="fn">Joe Doe</div>
<div class="org">The Example Company</div>
<a class="url" href="http://example.com/">http://example.com/</a>