I do find it ironic that we collectively freaked out about lead poisoning and got rid of the lead in paint. Except, the lead actually inhibited mold growth, so now we've got a LOT more mold. Lead is dangerous for certain groups. Mold is dangerous for everyone, and we're still figuring out how bad it is. I suspect that when all the dust settles, we'll be wishing that we still had the lead in the paint.
Asbestos is dangerous if you're breathing it in, a lot, for a long period of time. Which means construction workers. Even if you make a big dusty mess for a week or month, that isn't going to cause cancer. Wearing masks to help filter the dust is wise, but I do that when I'm mowing the lawn. Dust + breathing = unhappy lungs, regardless of the type of dust.
Lead is dangerous if you're growing a lot. Babies, little kids, pregnant women. The paint on the wall isn't really a huge concern, it's the lead in the pipes. And if the water main has lead, it doesn't matter what's going on in your house, you're getting lead. Eat a healthy balanced diet that includes lots of green leafy things, that will help. Clean up/contain the dust and debris if you're working on something, and wear a mask because dust + breathing.... If you sand and refinish the floors, go overboard on containing the dust (it makes a mess, and the finish often contained lead, so quantity concerns)
Radon is dangerous if it builds up. Anyone notice that radon wasn't really a concern until recent decades? It's because houses have become more and more airtight, trapping the radon in the house. If your house was built in the 20s, my guess is it's not airtight. You've probably got enough natural air movement to take care of it. If you shut down that airflow, you need to replicate it somehow because you'll destroy your house with mold and mildew, which will make you sick long before any radon will.
OP, yes everyone freaks out. In most cases, it's silly. It sounds like you guys are new to older houses. Honestly, I'd be more concerned about tetanus. Go get a booster.
If your wife isn't comfortable, then you've really got 2 options:
1. Get her evaluated and treated for anxiety. Because these worries seem excessive to me. You're not talking about high risk conditions.
2. Don't buy an old house. What you're talking about comes with the territory, and if you can't handle this then you have no business in this particular house. Of course, you might be worse off with a new house based on some of what I've heard.