The original. It's classic. Nothing much new to review here. One of the best movies of all time. Period.
Yes, watching AVP made me want to go back and check out the original Alien. And you know what? It's still awesome!
I actually watched it with Ridley Scott's 1999 commentary track this time and it was amazing. Some commentaries are such bullshit with the actors and director just talking and laughing about what a good time they had on the set, but Ridley was so informative. I learned so much about this film as he gives you insight on everything from the script to the casting to the production design to the special effects to Giger to the minatures. As it was only his second film, I never realized how low budget Alien was because to this day it still does not look it all. Even he says that it's a testament to how much pride and care the cast and crew put into every aspect of the movie. It was really just fascinating. Highly recommended!
There was one point where Ridley was talking about how one day he really wants to go back and make Alien 5 or 6. I found myself shouting "Then why don't you?! Please!!" at the screen.