If your hearing clicks when your hard drive is working more than likely the read/write heads are damaged inside your pc and certian parts of your disk will no longer be accessed to.
This being said sometimes you can save the drive your working on by doing a disk check.
Do the following to test:
go to start
click my computer
right click on your hard drive (c:\)
click on properties
click on the tools tab
and do a disk check - click "check now"
tick the two check boxes
click ok
This will give you a message saying to do it when the computer restarts - click yes
reboot your computer
this will then start the disk check when your computer reboots and try and repair any damages that may have come onto your hard drive. Hopefully any lost information will be rescued and moved to a safer part of your hard drive.
If this doesn't work try having a look at the Ultimate boot CD.
This cd is free to download and lets you do test features on broken hardware equipment. Such as RAM, Hard drives, CD-ROM, etcs... basically burn it to a CD and then stick it in the computer when it boots up.
Have a look here: http://www.ultimatebootcd.com/