The first thing we notice about Chapter 5 of Genesis is the prominence of both genealogy and chronology. While the seven generations of Cain's male progeny were listed in a couple of verses (4:17 - 18), the ten generations from Adam to Noah (by way of Seth) are treated in longer, more formulaic fashion. Also, for the first time in the Bible, we're seeing chronologies: each man's lifetime is broken down into years before and after fatherhood, and fnally (and redundantly) the total lifespan. The wording is identical in each case, except for Enoch, who mysteriously "walked with G-d" but did not die, "for G-d took him."
(Incidentally, the wording of "Enoch walked with G-d" is repeated identically with reference to Noah a few verses later.)
The lifespans of the early generations are clearly fantastical relative to our own experience. Most commentaries simply pass by the numbers with a shrug of the shoulders, but it might be worth wondering if there is some symbolism hidden in these numbers. I am not talking about gematria (Hebrew numerology) because I'm not convinced that this idea was prevalent in Biblical times. But it is certainly true that Biblical man understood the process of reckoning with numbers; as I've already observed, there are a great many numbers in the Bible, beginning with the counting of the days in the Creation narrative. It would have been impossible to keep a calendar - a theme we'll return to again shortly - without mastering the theory and practice of multiplication, for instance.
Speaking of multiples, the final verse of this chapter (5:32) reports the first multiple birth in the Bible: Shem, Ham, and Japheth, who were born in the same year to the same woman (Noah is not recorded as having a second wife or concubine) and so must have been triplets. (Or conceivably, twins separated by less than a year from a single birth.) As we saw earlier, this woman is held by tradition to have been Na'amah, the daughter of Lemech and Zillah and a descendent of Cain.
It's also worth noting that Noah becomes a father late in life, relatively speaking, compared to his ancestors. At 500 years old, he is past middle age (500/950 = 10/19) when he begets his three sons.
You can't help noticing that the names of Seth's descendents often parallel the names of the line of Cain. I haven't the time or space to devote to a full treatment of this subject, but Zvi Grumet has a very interesting take, in which the descendents of Seth try to avert the curse placed on Cain's descendents (pp. 72-73). The meanings of the Hebrew names take on symbolic importance in Grumet's interpretation. I recommend getting Grumet's book to read the details.