I believe we're coming to a resources-crunch within the next 100-200 years that will result--one way or another--in a massive drop in population and a fundamental change in our society. Let's just hope we survive it.
I don't believe this, and you didn't give any kind of evidence for this.
Speculatively, I think the opposite is far more likely: Not only will oil, minerals, etc. not run out, but technology will advance quite rapidly, so it will be less and less an issue. I think the big threat is unrelated sociopolitical developments that constrain freedom, innovation, and technology.