I'm including multiples from the same series as one for reason that should be obvious.
(In not particular order)
1.Ghostbusters
2.this is kinda a cop out, but they would take most of my top ten some I'm counting the Back to the Future, Star Wars and Indiana Jones franchises all in second place.
3. Aliens
4.That Thing You Do
5. Princess Mononoke
Honestly I could make a top 5 in pretty much every genre from 80s and early 90s movie because I think there was like..a 12 year period from 82-94 that is probably the best decade(ish) of all time for movies but that would be a boring list. I need to be able to list more! Maybe a top 25. Or a top 5 by genres?