QuickBasic dos to YouTube video.

I have some programs written in quick basic dos environment. I want to get the output to a video file and put a voice narration over it and ultimately upload to YouTube. Can I take the cable that goes to the monitor and somehow use that signal as a video input in some video device in order to create a video that I can input into a video editing program in Windows 7? Any ideas? Best way to proceed? Thanks in advance for your help.