Can anyone let me know which of these I should try to get rid of/are harmful, and which are just normal system processes I shouldn't touch?
Based on the hijackthis log, I can't find anything suspicious
Please download HouseCall and scan your machine. Send me the log file or a screenshot of the windows showing if there is any infection:
Download and also scan your machine with rootkit buster tool, it may help to tell us if you have a rootkit/keylogger
You can also download and install this small program that will tell you if you're machine is a bot (part of a botnet) or not:
No update. Case closed.