Thanks for your fast response.
Yes, I am unable to change the number of posts displayed in the widget area....however, this is intermittent. I have managed to change the number a couple of times, but as soon as I log out it reverts back to showing the standard 5 recent posts. Even then, it's not consistent. I have tried a couple of times today after logging in to set it to display 10 posts, but it won't.
This only happened after I upgraded to V3.7.
I have not tried disabling all the other plugins because I don't think that is the problem. It looks like the upgrade is responsible, because I have not changed anything in my configuration since 3.6.
And as I am having the same problem as everyone else with the image display inside a post editing box (cannot see the buttons to edit an image and there is a long blank space where the image should be if we put a comment), I assume it's because the upgrade to 3.7 is at fault.
This is the link to my page: