Mary is there two problems ? the overheating power adapter and the ransomware . As for the power adapter how hot is it and does it get that way when you first turn it on or does it take some time to heat up? Does the computer seem to run hotter as well ? Does it seem to be harder to plug in to the laptop?
The ransomware is an ongoing problem that is a hard fix . The fixes that are out right now are not that effective and can end up with you loosing all your info. what I would suggest to you is buyng a new hard drive and having a new OS installed ,start fresh and setting the old one aside until a fix is found to rescue you info safely. If there was not any important data on the computer or you were smart and had it all backed up, you can just reformat it and that will wipe the drive clean and a new fresh OS can be installed. At this point in time there is no safe fix that can guarantee getting your info back