Feel good 80s movie.

Sorry, I can't think of an obscure one. You need a real film aficionado like BillHicksFan or Allaby to weigh in on that.

Some non-obscure, fun 80s flicks:

Trading Places
Beverly Hills Cop
Ghostbusters
Fletch

I haven't seen many obscure movies from any decade, and nearly all of them that I've seen were laughably bad. The only obscure one I can think of that I really liked is Cohen & Tate (1988), but I wouldn't call it a "feel good movie."

I rented it one day in the early 1990s after browsing for about a half hour and not finding anything I wanted to rent. Finally I decided I was just going to pick a movie at random from the section of the store I was browsing, and it happened to be Cohen & Tate, which I'd never heard of. I ended up renting it quite a few more times over the years. After the video rental store closed in the late 2000s, I looked for it on DVD, but it didn't exist (the DVD wasn't released until 2011), so I bought a VHS copy of it. In 2013 Shout Factory released it on Blu-ray, so I bought that.

Night Of The Comet (84) is a great silly 80s movie. Return Of The Living Dead (85) is lots of fun too.

Both are pretty well known and loved by horror fans but most others seem to have not heard of them. Neither is scary but they sure are good fun.

I suggest you try,
84 Charing Cross Road (1987)
It stars Anne Bancroft as New York writer who has a love of rare books and Anthony Hopkins as a London bookseller who correspond by mail over a two decade period of time.
I wholeheartedly recommend this film.

The Best Of Times (1986) with Kurt Russell and Robin Williams

https://www.imdb.com/title/tt0090713/?ref_=nm_flmg_t_42_act

I don't know if it qualifies as "obscure."

Mischief (1985)
Cinema Paradiso (1988)
Big (1988)

Pee-wee's Big Adventure
A Fish Called Wanda
Midnight Run
Real Genius

My Bodyguard 1980
Seems Like Old Times 1980
Deathtrap 1982
Blame it on Rio 1984
Valley Girl 1983
Johnny Dangerously 1984
The Great Muppet Caper 1981
Dragonslayer 1981

1987'S GREATEST COMEDY!.....MANNEQUIN.