To start OneNote
On the Start menu, point to All Programs, click Microsoft Office, and then click Microsoft Office OneNote 2007.
To open a notebook
On the File menu, point to Open, and then click Notebook.
Browse to the Documents\OneNote Notebooks folder.
Click (don't double-click) the folder representing the notebook you want to open, and then click Open.
To close a notebook
On the Navigation Bar, right-click the button of the notebook you want to close, and then click Close this Notebook.
On the File menu, click Close this Notebook to close the active notebook.
To display or hide toolbars
Right-click anywhere in the toolbar area. On the context menu that appears, select the toolbars you want and clear those you don't.