Q u o t e:
Have you gone through your Interface Options and looked through the options under the "Objectives" category? I forget if there are any settings that would have an effect on these features, but it would not hurt to start there.
If there aren't any options there, then I would suggest going through with a full reset of your User Interface. To do this, navigate to your World of Warcraft directory and delete the Interface, WTF and Cache folders found therein.
For more in-depth instructions, please check out this Support article:
Common Display Issues
http://us.blizzard.com/support/article.xml?locale=en_US&articleId=20377
