You can use the built-in Capture feature of Video Edit Magic to capture video from Web Cameras, Digital Video Cameras and Camcorders (generally video devices that produce live video or record videos to a tape).
Videos on a DVD, on the other hand, are already stored in files. The extension of these files is ".VOB". If the DVD is not copyrighted, you can browse the DVD in Windows Explorer and copy all VOB files from the DVD to your hard-drive. You can then open these VOB files with Video Edit Magic.