Brave New World is very complicated, but basically it's a dystopian future wherein humans are not born, but made in batches. They are manipulated genetically and behaviorally to an extreme degree to perform the tasks that the economy demands of them. Elements like intelligence, individualism, and compassion are bred-out because they are unnecessary. At the same time, they are made to take absolute pleasure in their work and other artificial outlets, resulting in something quite terrible: a perfectly happy and content slave.
Also, The Matrix should never be included in serious discussion because there is nothing in it that wasn't ripped off verbatim from somewhere else. Instead of talking about an idea from The Matrix, talk about the book the idea really came from.
EDIT: Apologies for nit-picking, but it's "Brave New World", as opposed to "A Brave New World." I know it sounds silly, but the title is from a quote that does not include the word "A."