The safe mode is part of the story and without a story I can't ask about canned air, if reloading the OS returns it to full speed and why any mention of drivers after years of use? It's not like drivers wear out.
No idea why it is doing this but I can log into a user account and use the computer perfectly fine for 5 minutes while programs are loading but as soon as everything has loaded the computer goes unbearably slow everything stops responding and it takes 10 minutes to load up anything. Computer works perfectly on safe mode but I'm sure its not a drivers problem. I have tried lots of things but nothing has worked