Honda Generator guy here...
A 2kw unit will run the basics. A 3kw will run more, and you won't have to unplug the fridge in order to run the microwave. You'll need a 4k unit if you require 220V service (some well pumps).
Traditional-design (non-inverter) models are cheaper, but have to run at 3,600 RPM to make 60hz power. Noisy, and terrible fuel consumption, but cheapest to buy, and a reasonable choice if all you want is stand-by power in an emergency.
Inverter-type generators are more expensive, but run at lower speeds and make 60Hz power just fine. This means quieter operation and better fuel consumption. The power profile is very good, almost what you'd get from your power company. Inverter type units are a great choice if use for camping, RV'ing, powering expensive electronics, or if you just can't stand the noise of an open-frame contractor-type unit.
Backfeeding power through a dryer outlet or the like is illegal and very dangerous. Sure, you might say, "But I know what I'm doing." And how about your wife? When you are out of town and power goes out, she's going to try and rig up the generator "just like I saw him do once" and ZAP if the power doesn't get her, it will probably bite the poor lineman who's down the street working to restore power and HE gets ZAPed. If none of that convinces you, then try explaining your "backfeeding" set-up to the insurance guy after the fire trucks leave.
If you want to use your home's wires with a generator, get a Transfer Switch ($150-$500) and have it installed by a licensed electrician according to code. The Transfer Switch will safely disconnect the circuits from the utility company THEN connect them to your generator.
Or just run some extension cords and power strips off the generator's outlets. Easier, cheaper and still safe.
Finally, it will seem elementary to 99% of us, but no matter how much you spent on that generator, and want to protect it from thieves,
don't run it inside, and that means a garage or basement, or near an open window. Gasoline-fueled generators produce poisonous gas (even the fancy Hondas), and you can't see it or smell it, but it can put you to sleep in minutes and you will never wake up.
