I'd recommend 'Fahrenheit 451'. It makes you think about the importance of books and knowledge. 'The Handmaid's Tale' is another great one. It's a very powerful story about the oppression of women in a dystopian world. And 'A Clockwork Orange' is quite unique with its own strange language and exploration of human nature in a bad society.
Sure. '1984' is a must - read. It has concepts like Big Brother watching you that have become iconic in dystopian literature. 'Brave New World' is also excellent. It's very different from '1984' in how it shows a seemingly happy but actually deeply flawed society. 'The Hunger Games' is really engaging as it has strong characters fighting against a cruel system.