Repairing Walls Prior To Rewallpapering Bathroom

[aerochago]

Our bungalow was built in 1933 and its about twelve years since i last stripped the paper off in the bathroom. We have always suffered with condensation and mould especially round and under the cistern. Higher up on the walls they are not so smooth now and rough to the touch in places. I want to seal/paint the walls prior to papering so what should i use?
Regards
Alan

 

[Robbie uk]

The pictures show that there is distemper on the walls, (the green bit) After a thorough sanding and filling, give the walls a coat of Zinsser gardz, this is specially made for this type of surface.

 

[aerochago]

What about the areas where the plaster has a rough finish higher up on the walls will that seal there?
Alan