Some of these have also come up previously -- but indeed they're interesting scenarios.
#1: I went down kicking and screaming on this one, because it seems like the batter should get a single, but my recollection is that the correct ruling is FC.
#2: Not a fielder's choice. OBR: "FIELDER'S CHOICE is the act of a fielder who handles a fair grounder and, instead of throwing to first base to put out the batter runner, throws to another base in an attempt to put out a preceding runner"
I don't think you need any particular scoring term to account for his advancement. He simply advanced on the play.
#3: From a scoring standpoint, this seems to be identical to #1. Again -- certainly unfair to the batter, but I don't think the rules allow for anything else.