I'd also like to recommend the Ken Burns "The Vietnam War," which can be found on PBS. It is amazingly well done and the depth of it is beyond most documentaries. For example, there is one episode (1.5+ hours) that covers a six month period from 1967 to '68.
I was a small child during the war (10 in '68) and (to be truthful) only somewhat remember watching the coverage on TV. My mother said I used to ask her if I was going to have to go fight there and that I didn't want to. Thankfully, I didn't. The war ended in '75. I had just turned 17.
Strangely, the My Lai massacre is not covered until a later episode. They slotted it in the time line where it was first reported --not when it actually happened. But be patient, they do get to it eventually.
The sobering part about the series is that it absolutely captures the stupidity, futility, and mismanagement of the war over such a long period of time. The huge waste on both sides. The scale of it was staggering.
Myself, I am always drawn to the jungle patrols and the combat portions, which are fierce, terrifying and totally engulfing. I can see why certain people are drawn to war. It's the ultimate video game. Everything is on the line. You have no idea what the enemy will do and (really, in the end) no idea what you will do when faced with that visceral terror and excitement. What a rush it must be! And how horrible too. I am in inveterate coward. I don't believe I would have gone if called, but my 17 year old self is someone I don't really know anymore.
Anyway, the series is great and I highly recommend it.