skeletonbow: I second OBS as a recommendation. May or may not work with all games, but it's worth trying. I haven't tried it with IWD2, but it is at least free to try it out.
Update: I installed IWD2 and tested it with OBS. There are generally at least 3 main ways to capture games with OBS. The first is "Game Capture" which attempts to intercept the framebuffer via DirectX/OpenGL et al. That does not appear to work with IWD2, however both "Window Capture" and "Desktop Capture" work perfectly with this game. It's best to have a multi-head setup for testing this stuff and being able to see the results as it is happening.
Hope this helps.
