Toolbar disappeared

Go to Window => Toolbars =>

Place a checkmark on all three.

✓ Standard

✓ Document

✓ Common

Hope that helps. 

That is the Properties Window in DW.

Go to Window > Properties (or hit Ctrl + F3) then click and drag it by its name tab down to the bottom until you see a blue highlight. Release to lock it to the application frame.

or

You could try resetting your Workspace under Window > Workspace Layout > Reset 'workspace name' but if you haven't saved your workspace since making changes, that won't work very well.

EDIT: Unless you're talking about the toolbar across the top that allows you ton insert all kinds of html items. If that's what you meant, that is the Insert Window under Window > Insert (or hit Ctrl + F2). It may open as a floating panel, if so, click its name tab and drag it to the top until a highlight appears, then release. You'll then have a bar of items across the top, make sure HTML is chosen so the HTML items are available.