Hitler discussed the idea of suicide openly with those in the bunker with him. Suicide was something considered honourable in the military culture in Germany. A cyanide capsule was tested on Hitler's beloved pet dog to make sure it would work for when Hitler used his own. Goebbels was one of the leading members of the NSDAP (Goebbels became Reichskanzler upon Hitler's death) in the bunker with Hitler and he too, along with his wife, committed suicide after Hitler (and after they had killed their own children).
Hitler had been urged by members of the NSDAP to leave Berlin but he made it clear that he would remain in Berlin until the end so they knew that Hitler intended to die in Berlin.
The reaction of the German people was mostly one of indifference. Life in Germany at that time was basically a living hell and had been for quite a while since the Allies began their round the clock bombing operations and also since the Soviets had invaded. Most people were too concerned with their own misery and trying to survive to care that Hitler had died. Hitler's popularity by the end was nonexistent except among small groups of diehard fanatics. Most people kept their opinions to themselves, because if they had an opinion it was a hope that the war would end with his death, because the fanatics were executing people who didn't display the proper level of fanaticism.
Edit - If you want to watch a great movie about this period I would recommend "Der Untergang" or "Downfall" as it is knwon in English speaking countries as it is about the final days of Hitler and covers this topic.