That's actually getting kind of hard to do.
Many of the best super-hero movies are from Marvel. Others are from Fox. But Disney has bought both of those, and many of the titles have been pulled from Netflix and Prime, to be shown only on Disney+.
Ah balls.
Many Super Hero movies have tie-ins to other super hero films, which can make it confusing for anyone who simply want to "jump in".
Double balls.
If you really want to give comic book movies another try, I might recommend "Iron Man". It was one of the first movies in the Marvel Cinematic Universe (so you wouldn't have had to have seen others in the franchise). And, it had many elements that I like about the genre... decent special effects/action, mix of humor and drama.
I saw the first one and big meh.
I almost forgot... once set of decent super hero moves that is available on Netflix is the Batman trilogy series by Christopher Nolan (with Christian Bale as Bruce Wayne/Batman). They are a lot more serious than (for example) the Marvel movies... the director took a lot more grounded approach to them. (He's still a vigilante dressed in a bat costume and has fantastic gadgets, but there's no 'super hero flying', very little humor, etc.) The first 2 movies were good... Batman Begins, and The Dark Knight (the Dark Night has over 90% critical acclaim on Rotten Tomatoes, and won multiple Oscars.) The third movie (Dark Knight Rises) was, in my opinion, much less good.
Oh yeah - I think I DID see that ! :O and it was good too...
What about The Joker - is that in that series ?