Disk maintenance: You can launch Disk First Aid, which can be found in the Utilities folder on your hard drive, to perform checks on your hard drive and other forms of media (floppies, Zip disks, etc.). If you suspect your hard drive has a problem, you will need to boot the computer from the original installation CD that came with it and launch the copy of Disk First Aid that is located in the Utilities folder of that disk. The computer should boot automatically from the installation CD if it is restarted with the disk in the drive, however, to force the computer to boot from the CD, simply hold down the C key on the keyboard until the Mac OS splash screen appears. This screen will look like the regular splash screen except there should be a repeated image of a CD in the background to let you know that you have started from the CD. Once the computer has booted from the CD follow these steps:
• Locate the Installation CD on the Desktop.
• Double click on the Installation CD, opening its window.
• Find the Utilities folder on the Installation CD. If it is not in the main window of the CD, then look for it within the Extras folder or possibly within the System folder. The location will vary depending upon the version of the installation disk.
• Once you find the Utilities folder, locate the Disk First Aid icon and launch the program by double-clicking on it.
• Once the program has launched, choose the disk that you wish to examine from the list on the left (if the disk doesn’t appear, try refreshing the list by selecting “rescan for disks” from the drop down menus) and then select either the Verify or Repair button. Verify simply checks the disk to make sure everything is OK. Repair both checks the disks and fixes any errors that it finds.
• As the computer scans, a small list of what it is doing will appear in the bottom window of Disk First Aid. When the computer finishes scanning the disk, it will
either say “no problems were found,” “problems were found and have been repaired,” or “Disk First Aid was unable to repair the disk.”
• Should Disk First Aid be unable to repair the disk, you can either invest in a commercial program such as Norton Disk Doctor to attempt to repair the disk, or backup the data on the disk (if possible), and either erase the disk completely, or if it is your harddrive, erase the disk and perform a clean reinstallation of the System Software.

Should a program freeze: Should a program freeze or become unresponsive, hold down the Apple/Command key + the Option Key + the Escape key simultaneously. A dialogue box should appear asking if you are sure you wish to Force the program to Quit. Sometimes you can select “Cancel” and this dialogue box will have been enough to unfreeze the program. If this doesn’t work, select “Force Quit” and wait for the program to close. Restart the computer. If attempting to Force Quit the program fails, you will have to force the computer to restart, either by locating the reset button on your computer or by holding down the power button for 10 seconds until the computer powers down. Restart the computer.

Should the computer freeze at Start Up: Should your Macintosh freeze at Start Up, you most likely have an extension conflict. In order to remedy this situation hold down the Shift key at start up. This will disable all your extensions. Once the computer starts, navigate to the Control Panels folder within your System folder and launch the Extension Manager. This control panel allows you to enable or disable different extensions to try to resolve extension conflicts. It is best to create a new Extension set within Extension Manager before installing new software, so that if there are any errors after installation, you can simply restart with the Shift key held down and choose this Extension set to undo the harm caused by the program.
For more info on troubleshooting Apple computers: Apple maintains a rather thorough list of online support information at their website: http://www.apple.com/support/
Another good place to find information on troubleshooting your Macintosh is MacFixIt: http://www.macfixit.com