A way to do it with a frozen image would be a screenshot and then mspaint which with a touch screen would be able to draw on the screenshot in say a yellow paint brush to mimic what you see on football games when they show the plays on TV.
Without lots of programming, I am unaware of any software out there that is free or low cost that gives this feature to home users without the mimic of a screenshot opened in mspaint and touch screen controlling the paintbrush.
To get the screenshot you can have live video feed and press the ( Print SCRN ) button to grab a snapshot of the screen, and then create a shortcut on the desktop to mspaint and launch that and paste the screenshot to paint and then you can write on it with paintbrush with finger and a touch display.
To make it more advanced you could use a macro creator to turn a hot key on your computer, a key you might not use on a regular basis such as tilde key ( ~ ) into a capture, launch mspaint, and paste the image to paint a 1 keystroke feature.
Maybe others here have a better method, but thats all I can come up with. As far as the laptop getting the video feed from CCTV and being mobile, you would have to go with wireless transmission of video and you would be limited to range, and the cost would be expensive. Cheapest would be a camera rolling that is attached to the laptop to USB and grabbing a still of it and drawing on that such as if your out in a field and took an image of it and wanted to draw and point out where for people to go, or at a high school football practice and just recorded the play and you want to perform an instant replay slow motion and grab a still and draw on it to point out to players what happened or what should have happened or what to do next.
*If you want to record this process too with video and audio there is Camtasia and Fraps. I own a lsingle user license of FRAPS and it works well for video recording, but it stores uncompressed video, so afterwards you have to compress it. I use virtualdub to compress it afterwards which is free. *You need lots of open HD space for fraps as for it takes little time to make 20GB video files.
