CamStudio
CamStudio is able to record all screen
and audio activity on your computer
and create industry-standard AVI video
files and using its built-in SWF
Producer can turn those AVIs into
lean, mean, bandwidth-friendly
Streaming Flash videos (SWFs)
EDIT2
WeGame.com
This is for uploading screencasts of video games, but they also provide a free Windows software for recording games on the computer. Just start the software, launch your game and hit record.
Taksi
Game recording software similar to FRAPS but is open source and free. Can capture game screenshots or video clips of running games but without audio, in full screen mode with hotkeys.
Game Cam
Free software for making movies of your favorite games on Windows. It will automatically search for games installed on your computer and will create an individual recording profile of every game. Game Cam can capture game screen shots, videos in AVI as well as audio.
EDIT1
This ACA Capture Pro article explains the problem and contains a solution:
How to re-record other video files playing on the screen
Sometime people want to record playing
video with ACA Capture Pro other
movies and games, that they see
playing on the web or in Microsoft
Media Player, RealMedia RealPlayer,
Apple's Quick Time Player etc.. The
problem they face is that often these
players use video overlay for faster,
smoother playback of the movie. A
video overlay is invisible to Windows
screen capture software like ACA
Capture Pro, because it is handled by
a special video hardware. ACA Capture
Pro will then record only a solid
color block (usually pink, blue or
black, the so called "overlay key
color"), which is all Windows sees at
the place where the movie is played.
But all is not lost, the overlay use
for playback may be sometimes turned
off, at least temporarily for
recording.
The article offers the following solutions:
- Method 1: Disable "hardware
acceleration" from your video player.
- Method 2: Disable "Hardware
acceleration" from your display
properties.