How to close view panels is well covered elsewhere. However in your particular case I would recommend clearing out the UI layout completely and starting from a clean setup.
To do this, save and re-open your .blend with Load UI disabled. You can disable Load UI persistently, by deselecting the option in ⎈ Ctrl⎇ AltU> User Preferences > File, or temporarily, by deselecting the option available while opening a .blend:
Also note that opening a .blend with Load UI disabled will keep the current layout, so to get back to the default you will have to load your startup .blend (⎈ CtrlN) first. Or if you want the default default, press File > Load factory settings before opening your .blend with Load UI disabled.