As a "starter home" first time repairer, I have looked at how-to-books and whatever videos I can find. I am having problems with 2 separate doors. FRENCH DOOR- it's rubbing at the top corner,(one door is locked in place) but the bottom has a large gap, enough to see daylight easily. It was suggested to me to remove some of the original screws and replace with longer ones. I changed a couple, but it didn't help much. I've thought about putting cardboard behind the hinge like the 'TOH' video suggested, but the door gets lots of wind and rain from the southwest...and will it saturate the cardboard so I repeatedly have to replace it? The 2nd door- exterior door ("people door") into garage- The door latches shut but I can push it open with a gentle nudge( without turning the handle). I'm on my knees now,watching repeatedly, the opening/closing of the door, and it doesn't appear that the metal piece that the latch fits into is in an incorrect position.In fact, it lines up very nicely.
Re: exterior door
The French door sounds like it may not have been installed correctly, that is straight and plumb. if shimming the hinges will take care of the problem and you don't want to use cardboard you can always cut up a piece of plastic to make the shims.
The people door, your problem is most likely the latch plate. It may line up up and down but may be in to far so the latch is not being allowed to fully engage or extend. This sometimes happens when weather striping is installed improperly and doesn't allow the door to close all the way or there isn't a deep enough indintation throught the latch plate.
Re: exterior door
Playing cards work nicely behind hinges. Most playing cards are water resistant and you can add and remove as needed.
I've used these in the past and they work nicely as well
they're under $5 I think...even Amazon carries them. My local lumber yard had them on the counter which was the only reason I tried them. Worked pretty nice for the situation I had.
Theres pretty simple weather stripping for the exterior door bottoms you can buy that are adjustable up and down just by loosening and tightening the screws once you get the doors straightened out.