Buy your wife the Ball Book of Canning. That and the instruction manual that comes with your pressure canner will be all she needs. She can join the forum and we'll walk her through the process.
I am glad you found this forum too. I am delighted, as are others here, to share what I have learned over my lifetime. If I can teach or help others to attain their goals, that makes me happy.
Does anyone cold can anymore? Not sure why it's called that because of the boiling and sealing the jars, but that's how Mom taught me. I just do tomatoes and tomatoe juice because of the acidic content, and not sure how well other less acidic veggies do. We cut sweet corn off and freeze, as well as freeze dry the blanched green beans.
We pack the tomatoes down in a quart jar, place the lids with good wax seals and tighten the rings on, but not all the way, and place in a canner on the stove. Fill with water and allow to boil. I don't remember the times, but take the jars out and allow to sit, and the pressure difference sets the lids until you hear a pop. Then they're sealed. Tighten the rings and store on shelves once the jars are back to room temp.
So are the tomatoes cooked before packing? Do you just cut fresh tomatoes and pack them in the jars along with the juices that come out of the tomatoes?
We blanche tomatoes to get the skin off easily but they are only in the hot water for a short time.
We have even canned dry beans back when we were in hurricane country. We still keep a stock of them on the shelf. It only takes about an hour to process the beans.
Like Mike said. I have always heard there needs to be a certain acidic level to keep veggies frim going bad, even though sealed. I never have tried other veggies.