1. If you wanted to travel from Asgard to Earth, in what direction do you need to go?
The answer was shown in Journey into Mystery Annual #1:
You would have to go south from Asgard to reach Earth.
2. What non-mutant villain had his powers from childhood?
Giant Man and Avengers opponent, Whirlwind (aka the Human Top):
The Taskmaster, suggested by Forine is a valid answer, but I should have specified that we are talking Silver Age only here.
3. Excluding Uncle Ben, who were the first two non-villains to die in Amazing Spiderman?
The first two non-villains to die in Amazing Spiderman were Bennett Brant (brother of Betty Brant) in ASM #11 and Frederick Foswell who bought the farm in ASM #52.
4. Who was the Invincible Man?
The Invincible Man was secretly the Super-Skrull, as revealed in Fantastic Four #32.4
5. What villain was responsible for the death of Mike Murdock?
Something of a trick question, for Mike Murdock never really lived and thus could not die. Still, to Karen Page and Foggy Nelson, it would appear that the Executioner was responsible, and only Matt Murdock would know that he himself was responsible for his brother's "demise".
Phil gets #4 and #5 and half-credit for #3. Forine correctly answered #1 (which I thought nobody would get) and gets half-credit for #3.