Don't run disk utility from the Leopad disks.....May be it will entirely corrupt your files!
Wait...Why don't we try this, the hard disk is not loading. So here it is :Running Disk Utility
• Once on the Installer screen, from the first window and from the Installer Menu bar, select Utilities.
• Now choose Disk Utility from the Utilities menu.
• Click the First Aid tab.
• Select the hard drive icon displaying your Macintosh HD
• Click Repair. Disk Utility checks and repairs the disk. (Do this also, Repair Permission and verify disk)
• Once completed, quit Disk Utility
• Click on Installer Menu and reboot to your Mac Desktop
Please refer this also, may be this will help you
How to Install Leopad : Click Here