1) This was movie about young people, who danced in club. I remember man with dark glasses - singer. He sings (at the end song): "No! No! No! No!" (this is quite fast track). Important thing: "No! No! No! No!" is only twice in whole song (at the end every musical verse. Probably 90's years. There were unprofessional dancers.
2) I remember strange track. Fast chorus: "Lai lai dee dee" or "Lai lai lai dee daeee" - I heard something similar. This is chorus. Unfortunately, I don't remember other words.
3) This is videoclip from 90's years. Afro-American with boombox walked on the beach. He has red swimming trunks and sings "Ummala, ummala" (or something similar). Then other people sings "Hey! Ho! Hey!". This is probably chorus of this song. Something similar to disco or dance. 90's.
Similar to this song, but this isn't:
4) The music video is set in a mountains. The man jumps from first mountain for second mountain. The chorus sounds as "Ay lai lai lai", but name of band was similar to "Polaris 10" or "Polaris 18". English song.