How do you watch a movie? I do not mean, where are you sitting, or what snack you eat while watching. What I am asking is, do you watch actively or passively? Studies show that about 95% of people watch movies passively. They sit down, let the movie play and then decide if they liked it. The other 5% who watch actively have a different habit. Active movie watchers sit down, turn on their critical thinking process and then examine the movie which they are watching.
I explained this once to someone and he told me "that sounds boring, I just want to enjoy the movie". I tried to explain to him that was the problem, but I do not think he got my point. When we watch passively we disengage our discernment (something Catholics are forbidden to do!) and allow the movie to teach us (because we are focusing entirely on being entertained and not upon what the video is implanting in our heads). This is why so many people are misled by errors and lies from Hollyweird.
To watch video (of any kind at all -- not just movies!) is dangerous--you need to be aware of this. Studies have been done on the human brain which confirm what I am telling you. When we watch a movie our brains go into passive mode unless we intentionally activate our thinking process and critically examine the movie. Passive watchers may think that they "know their theology" but if they continue to watch passively, any falsehoods or immorality that comes up in the videos will be received passively and thus influence the person towards accepting these things. Those who fall to this will always degenerate into errant ways of thinking and end up making very bad choices in their lives because they cannot think clearly and critically about those eternal realities that truly matter (because they are allowing themselves to be catechized by pagans!).
When someone watches a video actively he can still "enjoy" it, but his first focus is not entertainment; his first focus is "what am I being told here?" It may seem to take out the fun, but it is comparable to saying it is not fun to eat if we have to verify that the food is not poisoned. It takes time to learn how to be actively engaged in a movie when we watch it, but we all know how to do this already. The same studies mentioned above also showed that when we read a book (a genuine book, not a store ad or a news headline) our brain automatically goes into active mode. We just need to learn how to apply that to a video.
Those who say that they are fine with watching a movie but do not like to read are likely struggling with this very thing. They are used to passive entertainment and not comfortable with active discernment. This all comes down to this basic principle: we are commanded to love God with all our heart, soul, mind, and body. This means that it is not optional to learn to be active when we view video media. We must do so; the devil wants to control our minds, and we must learn how to give them instead to God. Only those who work at doing so intentionally will ever succeed.