I would try saving my data then restore to factory settings
You may just have corrupt system files which can be restored to factory settings. It's roughly a half day job, but usually your computer will run a whole lot better afterwards. Since it formats the hard drive before proceeding, you need to back up any data you want to keep, and of course you'll need to reinstall any software you've added since it was new. It's a pain but it sure beats having the problems you describe.