That depends on HOW it's going to end...
Is the world going to be hit by a meteor? Is everyone going to just fall asleep & then die all at the same time? What happens at midnight exactly?
Alien invasion? Nuclear war? Is the sun going to explode or die out?
I think the way the world ends makes a difference on HOW I would react and what I would do.
Who I would have with me would be the same. My children. I don't need to have some last adrenalin filled adventure or anything. My kids are my world anyway, so as long as I have all of them near me, I'm good.