The many people and pundits in a frenzy over the supposed violation of free speech by North Korea need to get a grip and come back to reality. The fact of the matter is, freedom of speech is a concept adored by the West, but not the entire world, and at the end of the day it is a luxury afforded only by our prosperous economies. Dropping DVD's into North Korea will just provoke further conflict and possibly even incite violence.
I think it's kind of silly to send DVDs across the border for two reasons:
A. North Korean authorities will likely find them and case every copy they can obtain.
B. The odds of anyone in North Korea owning a DVD player are very very slim, possibly none at all, so that would make their efforts worthless.
Any activists doing this are trying to start something. It is a horrible idea to drop a movie about the assassination of a country's leader into that country. North Korea is a country that loves its dictators, and is not on really good terms with anyone and it would not do to poke the bear, as it were, with this.
While freedom of expression is hugely important and shouldn't be undermined by the bullying tactics of North Korea, there is more at stake for the citizens of this country than freedom of expression in cinema. Being in possession of the film, even accidentally would be likely to provoke a furious response and could result in execution.
This is one of the worst ideas I have ever heard. It reminds me of how some groups dropped propaganda during the second World War. The movie certainly should be made available to all of those who want to see it, but dropping it from the sky is more than overkill.