Normaly we use over hear a PAL system
You're missing the point. The Video Experimenter shield takes in composite video, adds its overlay and sends out composite video. Does your current camera/monitor setup use composite video?
There isn't a lot to show you have done any research yourself. Have you searched google/bing/whatever for Arduino+accelerometer or Arduino+rotary encoder? You'll find plenty of useful information. The playground (http://arduino.cc/playground/) probably has most of what you need. Start by getting each piece to work separately, then look at how to combine them.