Any generator hookup will be required by code to have special isolators built in to prevent energizing the "grid" from your house. This is a safety thing for the crews working on the power lines. We had an electrician wire up the heater, the well pump, hot water heater, kitchen, bathroom and workshop lights and outlets to a plug-in and circuit breaker box/isolator. When power goes off, we plug one cord into one socket and fire up gen set. Necessary stuff works, but we don't need a very big generator.
I prefer the NG or propane over gasoline or diesel. Gas and diesel will eventually "rot" and not be usable if stored long-term. NG and propane lasts forever in storage. Propane tanks are now made to be burried, so there's no unsightly tank in the yard, just some pipe and valves that are easily hidden by shrubs or an artificial "stone" made to hide septic cleanouts hidden.