Some general thoughts
I think Dawn of the Dead '78 is possibly one of the greatest horror films ever made. It's like...horror drama? It was my first introduction to Romero and zombie films and it left a lasting impression. I think the extended original cut is the best of the 3 edits, some people prefer the shorter theatrical or the Argento Zombi edit. Weird how Romero films always had a lot of drama and characterization, something you didn't see a ton of in other horror from that period...in that regard, Dawn is a lot more like Jaws than it is, say, Halloween. He was able to balance characterization with mood, atmosphere, and social commentary. Dawn is an epic film despite being made on such a low budget. I mean it feels epic. That's hard to pull off, and it's even more remarkable it has a feeling of scale, when much of it was filmed in that mall. There's a real sense of claustrophobia and hopelessness with the main characters. Everything feels very pointless after Roger is bitten. The ending is particularly fucked up, think about it. A pregnant woman in a helicopter with little gas or ammo. How far could they really make it? I once read some fan fiction set after the end, the helicopter runs out of gas, and Peter survives and takes the newborn infant as his son in the apocalypse, eventually meeting up with the survivors from Day of the Dead.
There's some other lesser known Romero films that get overlooked like Martin and The Crazies. Crazies feels like a rough draft or a dry run for Dawn in many respects.
He was a good editor too. And way ahead of his time in often featuring women and black people as key, well-developed characters and not just stock victims or stereotypes. That's something even current films still struggle to pull off. Romero did it without pandering, he just portrayed them as flawed human beings like any other characters.