From the home page, the post titles are clickable and blue like all the links within the post itself. When I click on the post title to that posts individual page, the post title becomes black and not clickable.
that means that, in the individual (single posts/archived page) page, the theme editor took out the link to the individual page. Makes sense, since you're already there.
It's no longer a link on the archived page. You need to add "div.post h2 {color:#286EA0;}" to make the header on the archived page the same color blue as the regular page. It sill won't be clickable, though - as it's not a link.