I seem to remember there being a topic regarding computer trouble, but for the life of me I can't find it.

Thing is like this: last night my PC started, out of the very blue, acting strangely. Everything is moving really slowly, despite a ScanDisk and nothing running in the background. In task manager, at processes, the memory usage shows up at something like 200K for Firefox, which is far below what should be.
I don't know what information to offer regarding the trouble. It came on out of the blue, the laptop is not overheating - not that I can feel it so and it's always on a cooling pad - . If you could help me diagnose this and maybe find a sollution by Monday, I would be very grateful - I use this laptop for work and I'm ears deep into a project right now...losing it would inconvenience me greatly -. I have back up of my data, but I need to work on this nonetheless.

probably autorun or other malware if not then check the processor or the ram.i think you should install another windows version

probably malware

Check autorun and services. Disable anything suspicious.

Did the laptop get knocked recently or fall? That could cause damage to your hdd and cause the issues you are having.

Check your RAM, it might be the fault. Run virus and malware scans. Use boot scan if available. If everything fails, reinstall OS, since you have back up of your work. Only you know your browser history and can tell if there is possibility of infection. If an infection is not the case and the re-installing does not work, then it is most possibly a hardware fault.