Discs I would clean with some sort of solvent, then wash it, then sand it (so you don't just move contamination around).
Pads are slightly porous, and burning only really works for DOT fluid. If mineral oil got on them, it's just easier to bin them and put new ones in.
I have got mineral oil on my disc and pads. I assume it's not too hard to clean up the disc with alcohol but do I need to replace the pads?