I don't own any Blu-ray discs, and have never watched any films in this format. For one thing, it seems you need a compatible TV set (mine is an old CRT one) and a dedicated Blu-ray player.
I'm wondering though whether it's feasible to play these discs on a laptop? My researches so far suggest that it might be, though one would presumably need to use suitable software - I doubt that standard VLC etc would do the job? If so, would any old laptop, eg from the Windows 7 or 8 era, be okay for this, or would I need a version with an advanced processor and so on?
Hope that someone who, unlike me, has progressed into the 21st Century will be able to answer this! 
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On a mountain range
I'm Doctor Strange