When nuclear weapons are used against the Martians, they capture the explosive force of the nuke, and smoke it! They use it like a balloon, and it gives them high-pitched helium voices. Fridge Brilliance kicks in when you realize that a hydrogen bomb really does produce helium as a by-product of nuclear fusion.
The Martians' "Ack! Ack! Ack!" language seems simplistic and a bit silly until you consider the fact that they have no lips or cheeks that would enable them to make more complex sounds. "Ack!" is about the limit of simple syllables one can make without any skin covering the jaws.
Additionally, the Martians shouting every word could be due in part to the thinness of their homeworld's atmosphere.
At the end of the movie, the Martians are defeated and Earth is saved… except dropped Martian rayguns are littering the world and could very easily be picked up by and used by looters and other unsavory elements.
Las Vegas is shown to be a full-blown war zone and total chaos during the invasion, and it's not even all that big a city. If the Martian Invasion was that bad there, can you imagine what must have been going on in either New York or Los Angeles? You probably wouldn't even survive 5 seconds outside.
The Martian Girl mask and wig were possibly made from the remains of an abducted human woman.
