A few comments:
1) What do you mean by the "maximum-temperature" line - how about during the medieval warm period when Greenland was, well, Green. I know certain climate scientists are doing their utmost to airbrush the medieval warm period out of the record, but the evidence strongly supports its existence.
2) And this year, at least, we've had some of the coldest winters around in an age. Variance is a bitch, it really makes it hard to detect trends. The trend at the moment for global temperature is probably down over the last 10 years, up for the 20 or so years before that, but it is really hard to extract trends when temperature measurements are so badly affected by heat islands and the like. And no, I don't trust the adjusted temperatures produced by Hadley et al.
3) We have a lot of fossil fuels. I was told as a child that Oil was definitely going to run out in 20 years, we still have at least 50 years supply left - and that is 10 years after it was supposed to have run out. Coal we have oodles and oodles of. The only good reason I can see for worrying about how much oil we use is the simple fact that we get so many derivative products from crude (plastics etc.) that might become much more expensive to make once oil has run out, but I doubt anyone on this forum will see the end of oil, and probably the next generation or 2 as well. Saving things for future generations is a quaint idea that has never worked. During the Napoleonic wars, people in Britain were encouraged to plant oak to use for building ships, which by the time it matured wasn't needed. By the time we are in a new ice age, we will have new technologies to heat us. They might be based on Nuclear, or a renewable like Solar, or they might be based on as yet undiscovered stores of fossil fuels.
4) Actually, at $130/kg, we have enough U235 to last us for another century. Double the amount you are willing to pay, and we won't run out for a thousand years. Thorium breeders or conventional breeders are interesting tech, but we should research them slowly because of the added safety issues, and the problems of high-level waste.
5) I am much more worried about other pollutants than CO2. The US uses more fossil fuels than Europe primarily because it is much less densely populated. Like for like comparisons tend to show that fossil fuel usage is pretty even across the developed world.