To delete your profile pic:

First go to your Xanga Profile Editor and click the little "» Profile Pics" link on the left:

http://www.xanga.com/private/profilepics.aspx

If you see your current profile pic - you should also see a little "Delete" link right next to it. Just click that link to delete your profile pic.

If you do not see your current profile pic - it's possible you're using a "remotely linked" picture (hosted somewhere other than Xanga). In this case, to delete your profile pic:

• First upload a new pic to replace your current one - click the link to "Upload Profile Pics »":
  
  http://premium.xanga.com/private/profileupload.aspx
  
  and follow the instructions to upload a picture from your computer (don't worry about choosing a good picture - you're going to delete it right away, anyway).
  
  
• Now delete your new pic - the pic you just uploaded should now appear in your Xanga Profile Editor. Just click the little "Delete" link to delete it, and you should end up with no profile pic on your account :-).