A picture would be really help us answer-
As far as the calcium staining or streaking an acidic cleaner as mild as vinegar or one that is stronger like stone tech restore would be a good way to start on he walls.
Use a medium stiff brush and a sponge to work the chemical and remove the streaking. Then use a neutral cleaner to finish.
As far as the wood stain stains-paint stripper should be all they need-
All that being said-I would recommend finding a bona fide stone re- finisher and hiring them to handle this work for you-