I've had my MacBook Pro for about 3 months. Recently the "pinwheel" has started spinning for about 15 seconds every minute or so, or whenever I open an app. The app is unresponsive, but I can still use the Dock, go to the desktop, etc. If I open another program while an app is frozen, then the new app becomes unresponsive too. It's not constant though. It happens every now and then and lasts about an hour. It seems to happen more with Safari, but all apps will freeze once I open them when it's happening. I thought maybe it was overheating, but the temp never goes much above 140 F. I ran the Disk Utility at startup and repaired a bunch of permission errors, mainly with files in Safari's folder. I then did a Disk Repair and it was finding and fixing a bunch of issues, and then finally said it can't repair the disk and to backup all my files and reformat. I haven't done much with the computer other than installing Adobe Creative Suite, Transmit, MS Office and a couple other programs. Not sure how it could have gotten messed up already. I'd rather not format, but I'm sure this error isn't a good one. Any ideas?