Handbrake x265 Optimal settings for ripping DVD
Summary response for summary question :)


CRF 20 will look really nice
8-bit (no advantages over 10-bit)
No tuning. Grain tuning is for grainy source (old content). SSIM is for testing.
No additional parameters needed.
VFR (same as source)


I could really, really, reallly go down the rabbit hole with a more detailed answer, but I'll leave it at this for now.