What to convert my videos to, x265?

[Helen Barber]

I own some bluray TV shows. I would like to convert them to a smaller format, but hopefully rerain 95% of the quality

Is handbrake and x265 the best to use?

Thanks

 

[Helen Barber]

I have a 16 core and CPU

I'm looking to convert a few bluray box sets

My goal, best possible quality at say 40%-50% of orginal size, if possible?.. Can I keep HD audio streams untouched? - True HD etc

Sorry, I haven't done this since the good old divx xvid days.

Thanks so so much

 

[Helen Barber]

AV1 is better than x264 ?