First of all, briefly introduce the main concepts of the workspace, project, perspectives, and views.
Then show how to import an existing project directory into your Eclipse workspace. Creating a new project is so trivial that people can figure that out for themselves even if you don't hold their hands.
Then, spend the remaining time on things like how to run your application from within Eclipse, how to run your
unit tests from within Eclipse, how to format code automatically (and where to configure the code style settings), how to run an
Ant script from within Eclipse, and how to navigate source code (Go to definition, call graph, showing the type hierarchy, etc.).
I'm not sure how much of this you can fit into an hour, but this is what I'd consider the most important aspects (more or less in order of importance) from a learning-to-use perspective.
Of course, if the goal is to just raise awareness of what Eclipse can do rather than teach the fundamentals that help people to learn to actually use Eclipse, the content should focus more on the juicy features rather than the concepts.
