I want a summary of each post to show on the home page but the page persists in showing the full posts, even though I’ve ticked the box “For each article in a feed, show summary”. The blog is here: http://landings.org.uk/
I’m sorry but you are posting to the wrong support forum. We cannot help you here at wordpress.COM because that site is not hosted here, our support docs do not apply to it, and we do not provide support for sites we do not host.
WordPress.COM and WordPress.ORG are completely separate and have different username accounts, logins, features, run different versions of some themes with the same names, and have separate support documentation and separate support forums. Read the differences here http://en.support.wordpress.com/com-vs-org/