Allright, first of all i recommend some general cleaning and registry fixes with the Program "CCleaner"
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Next Step would be Defragmenting the Harddisk (this is not deleting any files!)
This could take a while, but let it run.
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Next Step: Deactivate Programs you dont really use when starting up the PC
Press and hold the Windows button, then Press "R" (or just search for msconfig with the windows search function)
This should open a little box which is called "Run"
Type in: "msconfig" and hit enter
Go to the tab "Startup" and simply deactivate the Programs you dont want to start up together with Windows (Often results in a waaaay faster Boot time
(These are also the unneccesary "Processes" you were talking about).
Well, thats what i mostly do, it really hope it helps you out.
(This is just basic things you should do once in a while)