First of all planing the door should be your last choice in fixing this problem. To many people do this without checking whats really wrong. The problem isn't really moisture at all most the time. It's usually the house moving in temperature changes of the seasons. It's also the weight of the door on old hinges. Check your hinges for wear. Just grab the door edge and push the door up and down. If there is wear then replace hinges. If not make sure all the screws are tight. They loosen up over time. The heavy door will cause the top hinge to sag. Today all new doors come with a three inch screw for the top hinge. Those older doors should have two in the top and one in each of the others. If the door is rubbing at the bottom then put the screw in the bottom hinge first. Just use a cordless screw gun and don't strip out the screw. I use #2 square bit screws for good tork. You will feel the frame pull in. So just let it snug down a bit. Close the door and check your reveal (the gap between the door and frame). The reveal should be at least an eighth of an inch to a quarter inch. It should be even from top to bottom. After you get the bottom hinge done then do the top one. Adjust and close the door after each tightening of the screw. Ounce you get this done it will never really move again. This should help you without planing the door. Good Luck!!!

peel- Sorry to have raised this, but better you should know. If it's any comfort, I did something similar a number of years ago...and I should have known better as I worked in the environmental field. What's done is done and the good news is that you won't repeat this in the future. While I have a very healthy respect for asbestos, it's also important not to obsess about this. Anyone who has remodeled a house has probably created such hazards due to the prior use of asbestos in many products (flooring, adhesive, joint compound, ceiling tiles, furnace insulation, mortar for firebrick, etc.) If such exposures were uniformly dangerous, most of us would be dead. However, I like the odds in my favor: keeping future exposure to a minimum makes a lot of sense.

Be sure to sell or give away that beautiful old railing and not throw it on a heap. I happen to like it. But indeed, it might look better in black. The railing you have posted instead gave me some shudders. Quite a contrary style and not one I'd welcome in my home. Way too modern for a ranch home, is what comes to my mind. If you are really going to get a new railing, I like the one Judy proposed, although I wouldn't want it in white at your place. Perhaps in black and the railing that matches the wood of the stairs? Or maybe something like this?

As long as the yard grades downward, away from the house, there is no reason to be catching water near the foundation. (Doing that is akin to placing a drain high up on the roof. It would serve no purpose at all.) Yet pebbles/rocks/gravel invite water to penetrate into the soil, should there be any water there. I would get rid of all the rocks. They might have been used as landscape mulch. Some people are under the impression that it is a way to prevent weeds, but as you see, it's not. Getting rid of the rocks would allow you to develop hardscape and foundation planting in the normal, regular way.