If you want to set the default picture-aspect ratio n:m to 16:9, go to advanced preferences (CTRL+P), show all settings, Input / codecs > DirectShow > Picture aspect ratio n:m, and change 4:3 to 16:9. You can change the default 4:3 aspecto ratio:
This has been tested with VLC 2.0.8 and VLC 2.1.3. This will enable you to make a screencast without special software.
Step by step tutorial on how to record audio and video with VLC.
