My Intel-based imac keeps hanging my programs like Word and Excel, Chrome, Firefox, etc. I force quit, then try to re-start, but get spinning wheel. I try to shut down and desktop clears, but won't actually shut down unless I push the button. It's doing it every day, almost every time I go to use any of my core programs. I got a RAM upgrade, and an OWC Mercury Elite Pro HD to take the back ups, but am not particularly computer savvy, need help!! Oh - I also record a moderate amount of music in Garage Band - could this be clogging up everything?