I have yet to play MM. I have played a little bit of OOT, but I need to really play it again and to the end.
Both games are absolutely worth playing to the end, MM is such an insanely radical, experimental, haunting, brutal, tragic game too. Pure dark fantasy. it has one of the most horrifying easter eggs I've ever seen, if I saw it as a child I'd definitely be traumatised and unable to play it ever again.
The 3ds version improved a lot of issues on MM and it had a LOT of problems but it also massively fucked up some important parts of the game ironically so yeah....
OOT is fucking amazing to the end. the water temple is an ordeal, it's reputation is not exaggerated at all but imo the shadow temple is also cancer and aids and especially a certain mini dungeon before it too.
@Sentinel will have a lot to say I imagine but in terms of narrative, atmosphere, themes, music, characterisation, genuine horror especially psychological and major tragedy and sacrifices, the n64 zeldas are INCREDIBLE. Zelda peaked then and has never been better. late 90s to early 2000s were absolutely amazing culturally/artistically in hindsight.