Answers
The high school in Back to the Future was Hill Valley High. We came kind of close, guessing Valley View.
The final question answer: Charles I, Charlie Chaplin, Anne Boleyn, Eva Peron and Gram Parsons all had their bodies stolen, in whole or in part, after their death.
Thanks to my mom the Evita fan, I've seen the stage production of Evita, at the end of which a creepy Vincent Price-type voiceover talks about the mysterious disappearance of Eva Peron's corpse. The movie version left off this detail.
And thanks to Tim, I now know that two of Gram Parson's friends stole his body from the Los Angeles Airport and set fire to it in Death Valley, according to what they said "he would have wanted."