I'm an owner of a 24" 2.4ghz aluminum iMac which is a little over a months old. Lately I have been experiencing random freezing/lockup if I open an application or surfing the internet. Only way to fix the problem is I have to shutdown my mac and restart it. Now for the past week my iMac takes about average 17 mins to load to the desktop from either a cold boot or a restart. Anyone else has this problem or know how can I fix it?
Could be your HDD is failing. Could also be serious voltage swings coming out of your outlet. At an old worksite, we had a machine that took five minutes to boot Windows. We took it down to bench it and it fired right up and into Windows within 60 seconds. Took it back upstairs and 10 minutes... We eventually found out the voltage going to the surge protector was dropping below 100 volts and the power supply in the PC couldn't provide enough power to spin the HDD more then a couple hundred RPM so it took tens of times as long to load the OS.
could it just be *gasp* OS slowdown? try reinstalling OS X, after backing everything up, thats what i would do, then if something were still wrong, go applecare if you still have a warranty, and if that finally doesnt work, then just take it to microcenter or something