Genres: Romantic, comedy
Start: The movie starts with a plane scene where boy was afraid of flying but girl tries to cheer him up.
Middle: Both girl and boy are adults now and are good friends. Girl is cheerful but boy is kind of a serious person. The relationship is very tough for him, but for the girl things are comparatively easy.
The specific scene I remember is when the girl forces the boy to go with her to a separate kind of night club, where in middle stage people dance on similar steps and the girl is aware of the steps but the boy learns them after some trouble. And suddenly water comes from the stage on the dancers and later foam too. Their cloths become messy, but both of them enjoy it. I think boy was a little stressed before this dance.
End: I think they both fall in love in mid-between but refuse to confess. I think they even had sex once. I didn't remember the exact ending but it most probably is a happy ending.
Release year: Looks like a late 90s film or may be early 2000s.