If you've clicked on the "Todays Posts" or "New posts since last visit" you don't have the options that you listed. All that you have to click on either the title of the thread (which takes you to the newest posts) or the arrow that's at the far right (which takes you to the newest post, but in a new window). See image below.
Well, I would include images, but it keeps crapping out on me when I try to upload anything.