What I do, or at least try to do:
Change the oil before winter storage. Fill the gas tank and add sta-bil if you wish, but probably not really necessary. Do not run the engine unless you're going to be driving somewhere; cold starting an engine is about the hardest thing you'll ever do to it, where a great deal of the wear occurs. I think I read somewhere that for the typical car, 90 percent of the engine wear occurs within the first few minutes after cold starts, and the other ten percent at all other times when it is in use.
Running the generator per the manufacturer's recommendations is a reasonable idea. If you have power available and a decent (multistage) converter, leaving it plugged in will keep the house batteries in good shape; otherwise, get them fully charged and then disconnect them (physically) and they'll be just fine in the cold for a few months. Similarly for the chassis battery, of course.
Remove all food (and maybe TP etc.) and set mouse traps. If you have vent covers--highly recommended--leave one or two ceiling vents under cover ajar to get some ventilation.