Weird. I have no problems with windows 10. Then again, I don't use Cortana.
But the things you are describing does sound strange. Which driver programs did you use? I typically use Slimdrivers and Driver Talent for drivers. Should I Remove it to see if any crap was installed on my computer. And the gold standard CCleaner and Defraggler to keep everything neat. At the minimum, use CCleaner to do a registry check, and clean up your cache. Maybe check your startup to see if crap is starting up that you really don't need to start up, like Adobe stuff.