Rifftrax.com (some of the MST3K stars) has been putting out very good voiceover tracks for current movies. You might ask them what kind of licensing they needed to go through.
They probably don't need any license. What rifftrax is doing is selling you an mp3 with their own comedy on it. It is a completely new work. The customer buys/rents the companion DVD and then syncs.
That is slightly different than OP because OP wants to broadcast the movie, or at least the exact words. The exact words are what he needs to license, even if he does perform them himself.
If OP can figure out a way to teach people language by making his own rifftrax mp3 then he is in business. Good call prodigal_erik.
Rifftrax guys gave me an idea - what if I setup Amazon shop and will sell legal DVDs. People who buy DVD get access to the same movie on my website (invitation code). Will it work?
The reason why is at the very heart of copyright law. You need to learn this area.
Owning copyright to a work gives the owner EXCLUSIVE rights to distribution of that work.
Therefore, just because you sold a legal copy to a user via Amazon you do not have the right to broadcast the work on your website. Only the copyright owner can do that, because he has exclusive distribution rights. Your broadcast isn't authorized even though you selling DVDs is authorized.
Be careful with this stuff. In my opinion you are playing with fire here. The RIAA has no problems with burying people who distribute songs illegally. MPAA has done less of this, but you don't want to be the example.
That is slightly different than OP because OP wants to broadcast the movie, or at least the exact words. The exact words are what he needs to license, even if he does perform them himself.
If OP can figure out a way to teach people language by making his own rifftrax mp3 then he is in business. Good call prodigal_erik.