Experimental games/game installations with custom controllers often implement them using a gadget called a Makey Makey. (I have no affiliation with the makers of this product)
This is a small circuit board you can plug into a computer by USB. It emulates a keyboard, simulating keypresses when activated in various ways.
By connecting wires to the circuit board, you can fire off these keypresses when an object is touched or a circuit is completed.
To build the kind of track controller you show using this, you'd build a double rail out of a conductive material. The bottom rail would be all one piece, while the top rail would be split into (electrically insulated) segments corresponding to each zone where you want to show different content. Connect each of these rail segments to a different input on the Makey Makey.
Your handle/knob would itself act as a conductor, bridging the two rails in the section it's currently occupying, completing the circuit so the Makey Makey can detect which segment it's in and send a corresponding key press signal.
On the software side, any piece of software that can react to keyboard presses can be used to react to these signals (which casts a wide net! That's why they do it this way, to be compatible with whatever software you're comfortable using) — it could be a slideshow presentation or a webpage, or a very simple game built on an engine or made from scratch.