Developing an understanding of capacitor
What happens, if the switch is opened abruptly. I guess, the electric field between the plates immediately collapses and the electrons of the first plate, try "to escape" 


This is incorrect. Once you open the switch, the charge on the capacitor has no way to escape. The E fields stays constant and the capacitor stores its energy until some path is provided for charge to escape it.

(In reality, there is a leakage path through the capacitor itself, and the charge slowly leak through this, discharging the capacitor, but this is likely to take minutes or hours to happen)

A key thing to remember is that energy can't be instantaneously transferred in or out of the capacitor. Because this would require an infinite current to be applied. This means the capacitor voltage can't change instantaneously either.


  I consider the capacitor to be of "infinite" resistance thus not storing any energy at all. 


This doesn't make any sense. An ideal capacitor has infinite resistance and it still stores energy proportional to the square of the voltage across it.


  instead of an resistance a coil is used. I would expect the coil to produce a very strong magnetic field, however for just a short time.


If you put an inductor and a capacitor in parallel (or in series) you will create a resonant circuit. The behavior is somewhat more complicated than just a field being created and then decaying away. Rather, you will see an oscillation as energy is transferred back and forth between the inductor and the capacitor.