Night of the living dead is a Public Domain Zombie movie, yup that right it's free to download, sell or do what ever you want with. Here is probably the best review of the film form the Silver Screen Kid at Analog Medium.
"I’ve been dreading writing this review ever since I decided to do it. Night of the Living Dead has been discussed by horror fans and film theorists ad nauseum since its release in 1968. Constantly I hear and read about people bending over backwards and sucking George Romero pee-pee for making such a milestone classic in the horror genre. I’m not complaining (exactly). It’s just, like, enough already. Sure, the movie was timely as hell. Sure, it was cleverly disguised social commentary. Sure, it carved out its own niche in the horror cannon as a kick ass approach to the zombie genre. Sure it’s been imitated a thousand times, never replicated. But have you ever seen it??? Granted, it’s an entertaining movie, but is much more than that? I didn’t walk away from the movie thinking, “I’ll never look at my life, or movies, the same way again.” I was just like, “that was kinda cheap, but it was cool.” I much prefer the sequel, Dawn of the Dead."
"Before you start sending me volumes of impassioned flame mail, let me explain. I’m not anti-Romero. And I’m not anti-zombie (that much should be obvious by now). It’s just that I don’t think Night of the Living Dead is the end all zombie flick. There are loads of moments that completely take you out of the moment, causing you to question the validity of the filmmakers and their budget. Does anyone even remember the female lead, Barbra? Every time I watch the movie I end up yelling at the screen something to the effect of, “snap out of it bitch! Losing it isn’t going to help anything! Cry me a river!” And the dialogue is some scenes is downright atrocious. There’s needless repetition, cornball over-acting, and lines that sound like they were read straight off the page. That all being said, I like the damn movie. I just don’t put it on a pedestal."

"There are some really awesome elements to Night of the Living Dead. The cinematography and two-dimensional use of frame is impressive to say the least. That’s one way that it gets the most out its meager budget, by packing as much information as it can into a single frame. Also, whoever they got to play all the zombies did an admirable job staggering and lumbering around in the dark. I’ve seen tons of low-budget Italian zombie flicks that make me cringe every time I see a costumed extra walking through the scene as if he’s thinking about what he’s going to have for lunch, or the drive home. Plus, I always like a movie that kills all of the main characters. The end of Night of the Living Dead is quite unsettling, yet gratifying in a strange way. At the end of the movie you realize why you sat through all the cheesy dialogue scenes and are glad for having done it. All in all, I give Night of the Living Dead 8 out of 10 decaying corpses, mostly for the influence it had on the genre."
AnalogMedium Encyclopedia Zombica