I'm working on this blogsite:
http://www.college-path.com/

The categories widget seems to be displaying some categories in a horizontal blue bar with others in the drop down.

How can I get rid of the horizontal display?

Thanks!

The two are unrelated

the blue bar is your atahualpa category menu
IOW the blue bar is unrelated to the category widget

For removing the category menubar, see the built-in explanation in atahualpa: -> style & edit header area

I removed %cats and it removed the ENTIRE dropdown and horizontal blue category bar.
We like the drop-down categories....but not the horizontal ones.
Or I can remove all of the blue bar category options both the vertical drop-down and the horizontal.

I just want to remove the horizontal and keep the vertical.

It is confusing as to what you want with the blue bar. If you are saying you only want the categories that have drop downs then just use the WordPress menu system and build whatever menu structure you want. If that is not what you meant can you explain further?