Install and run a Full Scan with Malwarebytes
Uncheck everything in msconfig>Startup except AV: Startup Programs - Change
Do the same in msconfig>Services after Hiding All MS Services.
Type Scheduler in Start Search box, from right column choose Display all Scheduled Tasks, Delete each one.
Password your account in Control Panel>User Accounts and Log Off or Shut Down when you leave computer.
Now nothing can run without you running it.