First of all, don't think about treating a whole house of mold as a diy project - mold can be too dangerous to your health, and it would be best to call a mold remediation specialist to treat the mold and remove it. This is true even if the mold is not completely widespread, but even affecting just one room, or just a area of several square feet on a wall or ceiling. With that much visible mold, you can't be sure of how much mold is hidden behind wallpaper or on the other side of the drywall. Professionals will remove the moldy drywall and other building materials, spray to kill the mold and test the air to be sure that spores do not remain.
Moldy drywall will need to be completely replaced, because it is porous and there is no good way to clean out all the mold. Insulation in the wall may also need to be replaced. Solid, nonporous surfaces should be able to be cleaned.
You need to treat the reason the mold is growing if you don't want it to come back. Mold can't live without moisture, whether it is sitting water or high relative humidity. The mold remediation specialist will figure out the source of the moisture in the house, using sophisticated thermal imaging technology and moisture detectors. Healthy home humidity usually is in the range of 30-50%, and 60% and over will allow mold to grow.
Once the mold is removed and the moisture problems fixed, you should not need further treatments.