Thought we already went over this watching on your couch thing?
Get yourself a player, they can range from anywhere from <100 to few hundred. I picked up my popcorn A110 many years ago.. (just looked up the info in my gmail, orded on 2/13/09 -- so going on 4 years I have had it, works like a Champ, has played everything I have thrown at it for $215. Such devices can be had for much cheaper these days.
Shoot you want a cheap way to do it - get yourself a raspberry pi for $35 - lots of options for a remote
I can watch any video file on my server on any of 3 tvs in the house. Using the 1 popcorn hour, simple wiring av rec and component switch that runs my many inputs to the other TVs. I can watch either of 2 dvrs, my popcorn or my vhs/dvd/recorder - which have never done actually - its outdated etc on any TV in the house. Simple flip of switch to what I want to watch where.
Now the wife won't me spend the money on super remote I would like to get. But just using simple RF extender that is size of battery you put in your remote as battery I can control my popcorn from any room in the house, same goes for my dvrs.
No need to put any sort of disk in anything.. Be it I want to watch movie or video of my grand daughter - click click there you go menu driven listing of every video I have, every picture and my full music library. All from the comfort of my couch
I know you don't want to buy a new TV, or might not even want to spend the money on a player -- but hey get yourself a raspberry pi for $35 and there you go.. Your in this century for how to watch video
While a great suggestion, is definitely leaning towards the pricey/tech-savy side.
He could easily get a cheap upgrade for "everything"
(plug to TV, stream from PC ... done)