I'm only going to discuss the health aspects of GMOs, and not the sometimes immoral behavior of some companies.
We've been using GM crops since the early 80s. Since then, there hasn't been a single piece of evidence that GMOs pose more danger than non-GM foods.
Have you ever seen a wild sheep? No, you haven't. Because there is no such thing. We're not even sure where sheep come from. Because we genetically engineered the **** out of them over the past 10 millennia. The only difference between breeding a characteristic in/out of an organism through traditional methods and genetic engineering is that the latter is faster, more accurate, and with vastly more potential.
My only regret about GMOs is that we're not pushing them far more aggressively. Wish we can have a ton of tailored foods that attempt to do different things with taste, nutritional contents, as well as the typical uses in hardening the crops and reducing the need for pesticides. I'm sure we will in the future, and I look forward to it.
Here's a summary of current mainstream scientific thought.
http://www.loc.gov/law/help/restrictions-on-gmos/usa.php
Now I'm sure you can find some scientist who claims GMOs give you AIDS or something. After all, scientists are just people. But there is no evidence at the current state of knowledge of any diverse health effects from any available GM crops. It remains possible, of course, that some future product will pose a health risk, or that an existing product might have an undiscovered side-effect. None the less, I take 10000x the risk each time I get into my car, so I'm not going to fret over how every little thing may or may not affect my health.
Speaking of documentaries, I once watched one about an Obama conspiracy to turn the West Muslim. Is this GMO one made by the same guys? Because if that's the case, I'm definitely watching it.