Credits go to my pal Nightshifter for finding this out.
First - I am assuming you have VLC Media Player installed ( http://www.videolan.org/
) and whatever codecs and whatnot you need to play your media.
Run VLC Player (click on icon or use programs menu). Click on the Settings in the menu (or hit ctrl+s) - see image:
this will open the preferences window so you can configure stuff
Click on the Video option in the list on the left hand side.
On the right, under Snapshot - you need to fill in where you want VLC to save captures, so click the browse button.
In the Browse for Folder window - click Desktop in the folder list (at the top) then click Make New Folder. A new folder will appear in the list. I named mine screencaps.
Make sure screencaps is selected and then click OK
You will be back at the preferences window, make sure png (or jpg whichever is prefered) is selected for Video Snapshot Format
Click the Save button at the bottom.
Now play your video file or DVD. Find what you want to capture and hit the pause button. Then click the Video selection in the menu and look down for Snapshot and click it. A file will be saved in the folder you made.
Here's an example of what I get from a capture (quality and format has been changed, but not image size)
Ergo Proxy trailer =P (resized it to fit on page)