I'll second what Richard said. You're dealing with powerful forces. Electrical and building codes have a lot of seemingly unnecessary silly redundancy built into them for a reason. Every one of those foolish regulations is there because someone died. It is possible to take a lot of shortcuts and still feel confident that if you do everything properly, nothing can go wrong, and when the power comes back on, you can disconnect the generator so there was no evidence that it was ever there, so you're in compliance with all the codes. But there's a lot of risk in those if's.
I decided it was time for a generator after the April Fool snowstorm of 1997 in the Northeast took out my power for three days. I started out with the assumption that I could get a decent generator at Costco and do all the work myself, but after I did my homework, I ended up hiring a contractor who specializes in generator installation and had a 9 KW propane unit installed. I had the propane company install a couple hundred-gallon tanks, and a plumber install the piping (and get the necessary permits). I chose a manual over an automatic start for two reasons. First, during a thunderstorm, I don't want the generator connected to the house wiring, where it would be just asking to get nailed. Second, in a catastrophic event like a tornado, where the house is severely damaged and wires are hanging down, I don't want power running through them. The tractor batteries they use on these don't last very long, and when you have to go out to start it yourself, you become more aware of when the battery is starting to weaken. You also know when it's been running so you can track the number of hours and know when it's time to change the oil.
Consider the following: How much is enough power? Central air is probably a luxury, but a portable unit is not. What about the refrigerator(s)? How about hot water heater? Do you want to do laundry? Do you want to end up like Oliver and Lisa Douglas, always having to figure out what you have to turn off to turn something else on? With 9 KW, I can run anything I want in the house except the central air. This includes two refrigerators, dehumidifier, washer, gas dryer, water pump, two furnaces (oil-fired but with big blowers).
How much is enough fuel? I have a five-gallon gas can for the snowblower, which gets me through an entire winter, and that's a major hassle - keeping it fresh, making sure I have enough, keeping it in a safe place. I wouldn't want to deal with the quantities you'd need to run a generator for a few days. My 200 gallons of propane could get me through two weeks of steady use. If an outage goes beyond two weeks, I probably could call for another propane delivery but if something caused the power to go off that long, then most likely the propane company wouldn't be in operation. But then, for a disaster of that magnitude, probably the National Guard would have ordered me to leave my home by then anyway.
Are you and your wife willing to go out in the weather to start a manual-start unit? This was one inconvenience I was willing to endure for the reasons listed above. My wife still thinks the procedure for starting it is more inconvenient than sitting in the dark, but now my son is old enough to do the job, so that helps.
If you really want a cheap solution that gives you some emergency power, then I'd say to get a portable unit at Costco and some very heavy gauge extension cords. If you want something that lets you live a somewhat normal life (without central air), then call a pro to install a propane unit. If you want something in-between, then think about it some more and you'll probably end up with one of these two solutions.
Oh, and by the way, life won't be completely normal. If you have cable modem and/or cable TV and the cable network survives the storm, it will be running on backup batteries and probably will fail within 12 hours. POTS and DSL might last longer if you have a direct connection to the central office. If you have any UPSs, they'll probably get upset over the low-quality power and keep switching on and off and beeping a lot. The cheapest and the more expensive UPSs usually can be set to low sensitivity and run OK. But the ones in between will keep switching on and off until they die. A heavy inductive load like a small air conditioner or a dehumidifier will help stabilize the power.