2. I am a medical doctor and have my own clinic. Can I play movie DVDs in my clinic to entertain my patients while they are waiting?

2. I am a medical doctor and have my own clinic. Can I play movie DVDs in my clinic to entertain my patients while they are waiting?

No, unless you have the licence or permission of the copyright owners. The playing of a movie DVD in your clinic amounts to showing the movie (and all its underlying works) in public. This is copyright infringement if the showing is without the permission of the copyright owners.