Try the damp towels and other washing on radiator airers, so there is no risk to the radiator or wallpaper. It does make a difference to the atmosphere as does opening windows in the morning as FE said and checking that the heat is not set to high. We were told never above 15 degrees but I must admit it has been higher lately Wear a roll necked sweater or a fleece while the windows are open, it is surprising how warm they are.
If you live near a Wilkinson store, they have radiator airers that you just slip over and can remove easily when not in use. Other stores such as Tesco, with a Home department often have them too. Argos is not always the cheapest but can be easier if you hate shopping, of course! The radiator airers also mean you save tumble drying, especially at a time when the fuel bills will be high enough!
Oh to add to my last comment, I have had few days recently which have been sunny enough to hang washing out. Amazingly, when the sun does shine on snow it does dry off the washing but you still need the airers for a while. On sunny snowy days it is not too bad opening windows for a while. Practise deep breathing!