The content settings area is a global settings area where you can apply styles and settings to your entire site for the main content on your site, blog posts, galleries, slideshows etc.
The listings layout area has 4 options. The options to set the page featured image view, excerpt lengths for the grid view with text below, the archive list view (thats search pages etc) and pagination type.
The blog section allows you to apply some global settings to any blog page.
The first section you can set the blog listing layout, if using the options in Settings > Reading, other options include showing the dates on grid views, the featured image view (full width or content width), the option to show similar posts at the bottom of a single post, the distance between post images, the single post width and the background color for posts content.
The next section there more options for the blog pages, including the options to show categories, dates, tags and pagination on the blog page. You can also enable social sharing for your posts, enable auto set featured images, show the featured image in single posts, the option to show excerpts (thats a small text description) on blog pages, and the option for responsive images (its recommended to leave this option as disabled for all devices):
The last 2 options are related to comments. You can drag and drop the comments options into enabled or disabled. If using Facebook comment you should set up a Facebook application and enter the application ID:
The galleries section allows for global setting to be applied for your gallery pages and posts. You can enable dates for galleries and video posts, select the default slider type (if not selected when creating a single gallery), the slider height, distance between images for some of the gallery layouts, and also social sharing options for galleries:
The slideshow options allow you to add some global slideshow options to your site:
The following settings allow you to enable full screen slideshows on mobile (that is full screen height, be aware that your images will be cropped to a portrait format), otherwise you can set the height for the slideshow on mobile (300px recommended). You can also turn on the option to enable autoplay for the slideshow, select the arrow types for navigation. Transition speed and transition effect can also be selected here. If you want to enable pause on mouse hover you can do so (the slideshow will stop autoplay when hovered over). We also have the option to change the text color for the items over menu based on the background image. Finally, if using a visible nearby slideshow (a slideshow with images each side of the main image), you can set the space between images.
Finally there are options for slideshow typography. These are used when adding text over the slideshow, in the single slideshow options:
The pages section has 2 options for global settings. The option to enable the featured image at the top of pages and page comments.
The image size section is useful for changing the featured image sizing options for your site. Its particularly useful when optimizing the site as you can set sizes based on your layouts. If you’re usure of the options, click on the gold ? to the right to view what it changes.