For some reason my Macbook has been acting weird today. Since this morning, I've had Safari freeze about 8 times and iTunes froze once. Also, I went to shut down and it did everything it normally does (goes to blue screen and then off), but the little white light on the outside stayed on. I opened it up and the screen was still black and the fans were still running. I pressed the power button - nothing. So I just held down the power button until it shut down finally. Safari still froze after the reboot so now I'm here for help. This can't be normal... How can I fix this?