I hear Torrent sites are very popular for downloading full movies these days, and something called "Popcorn Time" is gaining popularity...
The problem is that, unless platforms like this are providing a service legally, then it's only a matter of time before they get shut down.
Instead, I try to find the best streaming services available, and pay a monthly subscription to enjoy films in good quality and without worrying that the site I'm using could be taken down at any time.
Netflix is one of the sites I use quite a lot, but there are plenty of other ones if Netflix doesn't show the movies you're looking for!