Cromalin has mentioned many good ones already, so I'll just add some I have watched. Beware of CWs though, especially in the OVAs.

Movies

Lupin III: Goodbye Lady Liberty (1989) - I'm a sucker for Lupin III yearly specials, and this is the first one they made. There's also a couple of others in the decade, most notably The Fuma Conspiracy (1987). 1978's Mystery of Mamo is also good.

Dagger of Kamui (1985) - Is an epic adventure movie with a very solid soundtrack. Not everything aged that well in it, but it's a fun watch.

Galaxy Express 999 (1979) - Is a very solid movie adaptation of a sci-fi adventure anime series from 1978 by Leiji Matsumoto. If you don't want to watch 113 episodes of anime, it's a good alternative.

Crusher Joe (1983) - Is a fun sci-fi movie by the creator of Dirty Pair (good show btw - the movie has a fun villain but is mostly mid). It also has an OVA sequel.

Hans Christian Anderson's The Little Mermaid (1975) - Why yes, a western classic adaptation. It's a well-made one.

Jarinko Chie (1981) - Is a charming and weird movie by the co-founder of Studio Ghibli Isao Takahata. All of the voice actors are also random people from the Kansai region.

OVA

Vampire Princess Miyu (1988, Horror) - Genmu Senki Leda (1985, Fantasy) - Prefectural Earth Defense Force (1986, Tokusatsu Parody) - Ultimate Teacher (1988, Wacky Action Comedy) - Digital Devil Story: Megami Tensei (1987, Edgy Horror & r/megaten meme classic) - Amefuri Kozou (1983, Drama with a younger audience in mind) - Elf 17 (1987, Sci-fi comedy)