Though upgrading or more hardware can always help, there's a lot of tweaks you can do that will make a difference.
Download Revo uninstaller and remove/uninstall all the programs and crap you don't use
Definitely ccleaner & malwarebytes.
Turn off system restore and delete restore points before running Malwarebytes.
I would never use it afterward either but your decision.
Disable MS Services (Control panel.administrative tools/services) such as Windows Firewall, Windows update except for when using on occasion, Security Center, Desktop Services, Secondary Logon, Remote registry, Error Reporting and optional services such as Bluetooth & touchscreen (unless using)
Disable or delete most/all your startup programs.
There's no reason most of these need to be started every time you are on PC.
Windows Defender...Go through the settings, turn this piece of shit off....it's worthless...kill it!
Folder options-Check Launch in a new process
Antivirus/Firewall software today is often bloated due to wanting to do 99 things other than just secure your computer.
Personally I don't use either but that may not work for you, depends on your online habits, browser config and porn viewing =)
Whatever you use, take time to go through the settings, only use what you need and pay attention to how you configure it.
Good Luck