|Press Ctrl+Alt+Del to bring up Task Manager, then click the Processes tab. Under "user name" you'll see SYSTEM, LOCAL SERVICE, NETWORK SERVICE & your own user name. I'll assume it's pdot42. There are certain services that can be disabled for better performance but for the most part, the only processes you need to be concerned with are the ones associated with pdot42. Put your mouse pointer on "User name" on the top of the column & click...this will arrange all the processes. You may have to click twice to bring your name to the top. The ones associated with pdot42 are the processes you need to sort out.|
On my system, I have 40 processes running but only 6 of them are associated with my name. I can identify all of them...explorer, internet explorer, task manager, sound mixer, firewall & anti-virus. If you have processes that you can't identify, google them...you may find they're legit, but they may also be viruses, malware or spyware. Once they're identified, you can figure out how to deal with them.
If you click on the word "CPU" at the top of the column, the processes will then be arranged by CPU usage. If a certain process is hogging the CPU, google it.
If you've only got 3% freespace, it's time to do some major house cleaning. You need at least 15% free space to be able to defrag. Do you regularly empty your recycle bin? Some people just leave stuff sitting in there, not realizing that until you empty it, it's still occupying space on the drive. I've seen PCs with dozens of GBs of junk just rotting away in the bin. If you're sure you don't need it, dump it.
And get a cleaner such as CCleaner-Slim...it's the last one of this list:
CCleaner can also help you to identify startup processes. Open CCleaner, click TOOLS, then click STARTUP. From there, you can either delete or disable unneeded or unwanted processes that load every time the PC is started.