noisy oil heat/hot water convector radiators

The house was built in the 70s and whenever the heat comes up, or at least in the morning, there are loud clanking noises and it wakes me up or keeps me up if I was already up and want to fall back asleep.  This wrecks my sleep and my health and this year I made resolutions for better health, which includes getting 7 to 8 hours of uninterrupted sleep.  I live with my parents who seem to not listen to me and sit home all day retired not finding out why the darn radiators make so much noise that feels like one of those NYC subway performers is playing one of those oddball "instruments next to my bed.  I have tiny bedroom and there is no configuration other than the bed lining the wall with the radiator and even if I slept on the other side of the room, the clanking is so darn loud it prolly wouldn't make a difference anyway esp since just outside my door is the hallway radiator.  They have a much larger room and I don't sleep in there to know what sounds their radiators make, but to some degree my parents can sleep thru loud noises much better than I can anyway. 

And it startles me to point my  heart is jumping, it will make the noises, then quiet for a moment and thank clank and my friggan heart jumps and you can't sleep like that, is like a form of torture. You try relax and then someone comes up and whacks something metal with a hammer startling you, this is what this is like.  It is like you hear the metal expanding or something.  I don't know, but are they considered old at this point?  Would it be possible to fix it or just replace at least the one in my room and the one in the hallway?  Or are some, or even most, of the noises due to the pipes themselves and replacing the radiators wouldn't be enough? I don't think my parents are going to tear walls down to get at pipes, they're in their 70s and 80s, but so far have not moved out and have let me stay here free so I know hard for beggars to be choosy, but like my health is at stake here, I already have like chronic fatigue syndrome and something similar to fibromyalgia, I struggle all day tired and in pain and constantly sick and I just can't keep being jolted from my sleep and startled early in the morning by the radiator, is there a way to break it or turn it off, I'd rather have no heat by destroying the darn thing and use just a plug in electric heater in my room than to continue the clanking and the disturbance.  But if it is the pipes to blame for most of it, then I have no clue what to do.