How should I modify to prevent from constant freezing (beach balls)?

There are several things that you can do to speed up and increase the life of your computer. The first I would do is repair permissions on you hard drive. Go to your Utilities Folder -> Disk Utility and select your hard drive or hard drive partition located on the side bar of the application. There will be a option to verify and repair both your disk and your permissions. This goes through all your system files and fixes small things that can slow down your computer. The second thing that I would do would be to upgrade the ram. Everything that you do on your computer needs ram and just bumping it up to 4BG could double your system performance. You can get a good set of system ram from OWC. You can also upgrade your hard drive. At anytime, you computer should have about 80GB + free on the hard drive that will be used from virtual memory. Link:

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