|Disk read failure and boot failure can occur when the computer is attempting to boot to a non bootable media. |
You are using a SATA type hard drive with WinXP. How are you configuring the hard drive in the BIOS?
If you are originally installing the drive using an AHCI (http://en.wikipedia.org/wiki/Advanced_Host_Controller_Interface) setting and that setting is subsequently reset for some reason then WinXP will not find the hard drive.
If you have disks in any removable drives or have USB devices in the boot order that could also produce the messages you are getting.
In short, there may be nothing at all wrong with either of the hard drives.
As was mentioned above the CMOS battery can be the problem.
When you reboot immediately enter the BIOS (setup) screens. If the date there is wrong then all the settings have been reset to defaults. If you originally used AHCI in the BIOS then reset it to that value and see what happens. You also need to set date, time and boot order. Possibly other items as required.
Where did you get such ridiculous numbers for HD failure rates?