Well, I'm not sure if Dallas gets any Hurricane style weather, but perhaps it does. I'm assuming that's what you mean, but perhaps you also mean TEOTWAWKI type scenarios.

Anyway, for bug in, I would definitely have plenty of rope and perhaps a pully system for raising and lowering yourself or your wife into the basement if she's unable to walk. Obviously an elevator would be best, but is both expensive and unreliable if no juice.

I would also have alternate mobility setup. I've seen people (and done it for kicks when working in a warehouse) pushing another person on a hand truck/furniture dolly. For your wife, this might be ideal if she is unable to get around. You could push her and make her verticle.

Now, one thing you may not have considered is a handicap accessible vehicle. With your situation, that might be a prudent choice. Even in a sudden event you could roll your prone wife or vice versa onto said hand truck and get the other around. Even if crawling is involved it's easier to carry someone on 2 wheels than to drag them along.

Off hand, I would say even in a sudden event you should have your mobility figured out. Hunkering down is less worrisome, but tornados could mean getting to the basement ASAP.

As for the rest, you're in Texas... make sure you have guns and ammo both in house and in vehicle. And I would have at least minimal supplies in your truck in case your are unable to bug out effectively. This should minimize your get-away time. I would have basic shelter, stove, fuel, food, and rotate water - say at least a weeks worth, which would be about 10 Gal. I would most certainly have radios, firestarting, knives and other standard survival gear. Make sure you duplicate it and keep it rotated through your truck as much as you can afford. Plenty of rope too.

For digging in, maybe have generator with fuel supply (or solar with batteries for minimal equipment like HAM). And a good amount of food and water.... enough for a month including sanitation.

Just my 2 cents. Maybe that will prompt more conversation. I have a cousin who is quadrapalegic, and I've never really discussed it with his parents about how he would get out, but it's still crossed my mind a few times. He's in a wheel chair and when out of it he can 'scoot' from place to place, but opening a door would be beyond his capability.

In the house, I'd sock away plenty of food and water (look at the long term survival board for more info)