With the 3rd largest population and the largest economy, we are inevitably the largest emitter of greenhouse gases (thus making the US a polluted country)

I also like Abraham Lincoln, and in the Philippines, I would say Cory Aquino had been good also since she really lead Filipinos gain their freedom from martial law

The best president ever? That's kind of a tough one. It certainly wasn't Abraham Lincoln though. What did he do that was so great? Launched a war which resulted in roughly 620,000 deaths? That doesn't sound so great to me. Abraham Lincoln = FAIL. Many people think he was great because he did it to free slaves. Hogwash:

"I will say then that I am not, nor ever have been in favor of bringing about in anyway the social and political equality of the white and black races [...] there is a physical difference between the white and black races which I believe will forever forbid the two races living together on terms of social and political equality. And inasmuch as they cannot so live, while they do remain together there must be the position of superior and inferior, and I as much as any other man am in favor of having the superior position assigned to the white race." ~Abraham Lincoln

I won't pick one particular president as the best. Even the better ones were not perfect. George Washington did great things, but still didn't believe in equality for blacks and was very rough on the Native Americans. One president stands out to me though.

Andrew Jackson: A big fighter against national banking establishments. He even managed to abolish the one in place back then. Unfortunately, another one just sprang back up again. So, we're still owned by few people who control the world's financial systems.