Welcome to Flyertalk redrook, welcome in particular to the BA board. We like to see new faces here and so I hope you will continue to participate here, despite the incident you had on the Vancouver service. I hope the rest of the trip went better for you.

I wonder if you are BAEC members? Sometimes Avios would be awarded rather than cash and that may be more useful. Instead of embarking on a legal process, which probably (OK almost certainly) won't get very far and could land you with BA's costs, how about ringing BA Customer Service to complain about it over the telephone? It may be they can come up with another remedy.

Faulty IFE does happen from time to time. From personal anecdote (but involving a lot of flights) it seems to happen less and less these days as the hardware gets more reliable and the duff systems get fixed or replaced. I can't remember a recent case where it was totally kaput (though I can recall a few outages mid flight) so I do think you were a bit unlucky. And no matter what airline you are on, it's always best to have your own IFE available as a back up.