090s came with either .404 or 1/2" chain, with .404 being more popular - that's why some wondered if it was a "G" at first, since 1/2" was more common on them. That's a good price on that drum too - I paid considerably more than that before shipping last year. You're going to have fun cutting with that saw, though your hands won't like it much. Get a nice long bar and stick it in some big wood though, or you might not be really impressed with its cutting ability.
I don't have kids of my own, but based on those in my family it seems that they will adapt to your lifestyle & noise far better than most think. My cousin and his wife were super-duper careful about being really quiet when the baby's asleep and being home at bedtime, and now the kid CAN'T (or won't) sleep anywhere but at home and the slightest noise wakes him. On the other hand, I can remember my brother being sprawled out on the floor asleep in front of the TV with a hockey game blaring when he was little.