|So you're pretty sure the crash was the hard drive and not some other piece of hardware? Are you sure you got everything reconnected right while you were inside the case--fans too?|
After you boot from the OS installation disk and it copies the files it should reboot and continue the installaiton. When it reboots and you get the 'boot from hard drive, boot from cd' option be sure to choose the hard drive.
Any error messages? Is the hard drive seen OK in cmos/bios setup and as part of the setup did you partition and format it?