I've had my iMac for almost 2 years now and I've rarely had any problems. However, in the past couple days... Safari crashes constantly Random applications won't open Random applications open, but have problems and get stuck when opening Computer won't shut down (just shows the desktop background and stays there.) Also, because it cannot shut down properly, I can't install updates I'll post more as I think of them. So is there anything I can do to fix this? Thanks!