It wouldn't be too difficult to pack a few hard drives or SSDs with a few thousand movies and episodes of TV shows. Ironically, while it would cost tens of thousands of dollars to buy all those DVDs and rip them, it would cost a lot more money to send the media holding the video files to mars. There would be a lengthy time-lag for emails, but that's little different than email is already.
Do not underestimate the bandwidth of a spaceship full of tapes!
I've noticed several design suggestions in your code.