Most should be self-explanatory. Note that if you click on the option there is often an explanation provided.

1. If False, your store will only send text emails, not HTML emails. That's my preference, but many disagree.

2 and 3. Leave at False unless you're having email problems.

3. Do you want to receive the admin emails in text or HTML format?

5 - 9. Do you want copies of the listed emails sent to some email address?

10. Never noticed that one, but I usually stick with the Zencart defaults unless I have reason not to.