I'll take a look at those. So it seems like no one has problem playing a game where they know the world is going to end and there is nothing they can do to stop it.

Well. The player might expect that their goal will be to stop the end of the world, regardless of what you might put at the back of the box. If anything, it's an issue of deception, but that can be a powerful narrative tool in its own right and I don't necessarily see it as a problem.

basically you have two choices

end of the world cannot be stopped = dystopia + depression + nobody wants to watch it
end of the world can be stopped = utopia action

it is up to you

I don't think you're that limited.

It really depends on how you want the player to view the end of the world. If you make other things more important and have that as more of a backdrop, then it won't be depressing for the player.

The player is fulfilled by accomplishing the goal for the game that you reward them for.

For instance, a woman that knows the world is going to end, and she wants to accomplish a list of things she's always wanted to do in the next week before she dies - the player's success is dependent on the list, not saving the world. Or... well, dating sims are a popular topic around these boards. Seven days to find your true love or something.

It may have a fatalistic flavor to it, but that's dependent on the atmosphere you develop.

Well once the world ends, everyone is gone, so do the last seven days of one person's life even matter? I am more interested in the aspect of the last man on earth. Zombie stories usually have the end of the earth and that one last survivor who finds people and repopulates the earth after killing the zombies and saving the girl. Or something along those lines.

Anywho, I like the concept of an end of the earth Sims type of game. Mabey the last guy is a computer genious who invents robots that know how to make more robots. And the player would have to take care of the robots motives while trying to develope a time machine that could reverse time back to a point where the end of the earth could be avoided.

So the hero goes back in time to save the earth. except he decideds he doesn't want to. Instead he saves the life of beautiful women in order to live with them (because he wants to be the last man on earth). Problem is, he changed the events of time by taking the women, so instead of paradise with robot servants and beautiful women, he has to fight zombies.

I like your game idea a lot! I think it would be a pretty cool game. Anyways, I think you should consider a time limit thing sorta like Dead Rising. Where you have a real 7 day time limit to do what ever you can. I also like what others have been saying about giving the players options. Maybe you can do something along the lines of Fable, where for every action theirs a conseqence. So a person can save the world, let it end, or save a few people in a bunker to preserve life. The only problem I see with all these options is a lot of work and space on a game. You would also have to have the setting of the game be in like one place like Washington DC instead of going all over the world. One last thing is how will the world end? Meteor, plague, etc. These are just some suggestions, take what you'd like. Great game story but it will be a lot of work deciding and coming up with the details of it. Good Luck!