Cannot read disk - Dell Dimension 2400 PC Desktop

"A disk read error occured press Ctrl+Alt+del to restart " FOLLOW THE BELOW INSTRUCTIONS TO RUN DELL DIAGNOSTIC ON INTERNAL HDD Open the Dell Diagnostics on either your hard drive (F12) or from the Resource (Drivers and Utilities) CD. Running from the hard drive is the preferred method of using the diagnostics. If problems occur when running from the hard drive or there is no Utility Partition, the diagnostics can be run from Resource (Drivers and Utility) CD. From your hard drive: Shut down and restart the computer. When the DELL® logo appears, press immediately. If you wait too long and the Microsoft® Windows® logo appears, continue to wait until you see the Windows desktop. Then shut down your computer and try again. When the boot device list appears, highlight ?Boot to Utility Partition? on desktop systems or ?Diagnostics? on portable systems and press . Note: On portable systems, PSA will be executed first. When PSA completes, press any key to load the Dell Diagnostics.? Go to step 2. NOTE: If you receive a message stating that no Diagnostics utility partition has been found, follow the instructions on the screen to run the Dell Diagnostics from your Resource (Drivers and Utilities) CD. From the Drivers and Utilities CD ResourceCD: Insert the Drivers and Utilities CD into the CD drive. Shut down and restart the computer. When the DELL® logo appears, press immediately. If you wait too long and the Microsoft® Windows® logo appears, continue to wait until you see the Windows desktop. Then shut down your computer and try again. NOTE: This feature changes the boot sequence for one time only. On the next start-up, the computer boots according to the devices specified in the system setup program. When the boot device list appears, highlight IDE CD-ROM and press . Select Boot from CD-ROM option from the CD boot menu. Select Run the 32 Bit Dell Diagnostics numbered list. If multiple versions are listed, select the version appropriate for your platform. Go to Step 2. After the Dell Diagnostics loads, the Main Menu appears. Click the button of the option you want. If a problem is encountered during a test, a message will display the error code and a description of the problem. Write down the error code and problem description and follow the instructions on the screen. If you can not resolve the error condition, contact Dell. If you run a test from the Custom Test or Symptom Tree option, click the tabs above the right window for more information: When the tests are completed, if you are running the Dell Diagnostics from the Drivers and Utilities CD, remove the Drivers and Utilities CD. Close the screen to return to the Main Menu screen. To exit the Dell Diagnostics and restart the computer, close the Main Menu screen. Regards Sunil Dsouza