New Choices?

I dropped in today, first time in several days and saw this "Recent Status" added to my left column. It didn't look like anything I needed and the LH column is getting too long as it is, so I opened "My Account" and edited things.

But after I did that I saw some things I didn't recognize. Something about "Share Content" with a bunch of settings/options; and "Activity Settings" with a subhead of "Privacy Settings" and "user replied on some content". This is the first time I've seen these, and I have absolutely no idea what they are for and what they are actually doing. For all I know if I do or don't check something or another, I could make everything disappear on my PC, never to be seen again.

So here is where I make a quiet plea: help!