I answered this as a question on Yahoo Answers a few weeks ago. The answer must be read frequently as several visitors come to this blog from there. So here is the full answer.
All the entries in the right hand column of this blog are "gadgets". You can add them as you want. But if you don't want one of them any more, how do you delete it?
"Sign in" to your blog at the top right of your screen.
Once you have signed in "customise" will appear immediately next to sign in (which should now say sign out).
Click on "customise".
Make sure the "layout" tab is selected.
Click "Edit" on the gadget you want to delete
The gadget editing box will open.
In the bottom left of this box, click on "Remove"