there are any number of stripping agents on the market if you want to try a stripper on the woodwork, doors and fixtures. For the fixtures, it's easiest to take them off the doors and put them in a container with the stripper to soak--but be careful not to leave them there to rust!! Woodwork: When my parents did this job in their old house, they used a combination of methods. First they used a heat gun and scraper to get through the thick layers of paint, then used a stripper to get the residue off. I have to tell you, it was a tough, time-consuming job. But the wood was gorgeous when it was done.
As for your walls, I'm not sure I understand. Is there paint on top of wallpaper, or just many years of paint? Is it peeling and chipping off? If there's no wallpaper, and there's no peeling going on, I don't know why you'd bother stripping the paint from the walls. If there's paper under the paint, well, stripping it all off is another hard job, and you have to be really careful of the plaster underneath it all, but it's well worth the work. If it's just paint, but you have peeling problems, I'd try scraping the areas where the peeling is happening to get all the loose stuff off, then use a fine sandpaper to sand it down level with the surrounding area, then re-paint.