Here's some of my favorite opening scenes, mostly classics I'm afraid:
Clockwork Orange. The music, the use of colors, the long close-up of Alex and then the slow pull back to reveal the bar and Alex's droogs, ending with the line "make you ready for a bit of the old ultra violence"...
[ame="https://www.youtube.com/watch?v=HI-mDTdeKR8"]https://www.youtube.com/watch?v=HI-mDTdeKR8[/ame]
Apocalypse Now. Just a perfect set-up for the nightmare that is about to be unleashed. The near-idillyc palms, the yellow smoke, the helicopters and then the napalm devastating everything, then the superimposition of Willard and the stone face...
[ame="https://www.youtube.com/watch?v=M4WJlLNIsyY"]https://www.youtube.com/watch?v=M4WJlLNIsyY[/ame]
Blade Runner. What can I say? The haunting music, the simple text, the futuristic landscape, the flames shooting up reflected in Roy's eyes. Beautiful.
[ame="https://www.youtube.com/watch?v=-fu7jN2_2pE"]https://www.youtube.com/watch?v=-fu7jN2_2pE[/ame]
Enter the void. This, well, you'll just have to watch it. And yes, the movie is just like that.
[ame="https://www.youtube.com/watch?v=tPxgi-PiNFE"]https://www.youtube.com/watch?v=tPxgi-PiNFE[/ame]