You shouldn't use a resistor between earth and neutral.
If it's a linear power supply this implies a transformer, rectifier, capacitor, setup and there is no problem connecting both primary and secondary to earth because they are not electrically connected, they are connected magnetically through the transformer metal core.
You are correct about some people connecting the -ve to earth and some don't, it's the same with 110v control transformers in larger installations.
One thing about having one pole to earth is that if there is an earth fault on the other pole it will blow the fuse but if one pole is not earthed the fuse will not blow because there is no circuit. In the second instance two earth faults have to be present, one on each pole before the fuse blows, it's then the same as shorting the poles together.