Oh just an update - haven't had time to DELVE DEEPLY into this but now weekend is coming. Today I turned my Mac Desktop on and eventually everything showed up but when I tried to use it the little spinning crazy wheel that makes me crazy too was all I got - it said that a program or whatever word it used was not responding and did I want to turn it off and i was gonna say yes but it prevented me from doing anything other than just enjoying the spinning wheel show. Do not know what's up with that but I am going to try to get into it this evening so if anyone else has had such a problem or whatever and wants to share. I'm gonna see what I can do tonight, read over the links for info you guys left here and see where I end up! Hopefully not the loony bin.
While your Mac is on, launch Disk Utility > choose the top level disc to check the S.M.A.R.T. status of the drive. If it isn't "Verified", back up your data because the drive is failing.
You could also Verify Disk with DU to see if there are any errors that need to be repaired.
Activity Monitor will show which process is causing the spinning wheel on your Mac. You can also Force Quit a process/app from the Quit Process button in Activity Monitor.
How much RAM and hard drive space does your Mac have?