New imac freezing. Help!
You have 90 days of free AppleCare telephone support, give them a call immediately. They will assist you on how to handle this, on a new machine it should work flawlessly. You can locate the correct number in your area by clicking http://support.apple.com/kb/he57
BTW, have you installed any antivirus apps or any apps to "clean" or maintain your computer. If so I suspect those are the source of the problem and should be immediately uninstalled because they are not only completely unnecessary but tend to waste valuable system resources and tend to create more issues than they solve. OS X is very stable if left alone, it does not require 3rd party tools to maintain it like MS Windows. The very best thing you can do for your computer is to keep it up-to-date by installing the recommended updates found in System Update.