Is my Hard Drive failing?

[rocky_gas]

Right so over the past week various programs have stopped working. It started with Firefox which said cannot be started because application.ini is missing, after countless times re-installing it each time it would eventually be missing a file and not be able to start. Similarly, whenever I click on any Microsoft office programs it starts windows installer asking me to reinstall them, the same happens for Symantec Anti-Virus. My Video card drivers have stopped working and therefore all my games produce errors and such when launching.

These symptoms all seem to be related to files going missing which is why I think it may be my hard drive failing.
Anyway, I ran a Chkdsk which reported no problems with the hard drive no errors or anything but took a VERY long time to complete.

So after all these problems I though to myself, better back everything up and reinstall windows. So, everything is backed up now, put my windows 7 disc and after the loading bar which says loading windows files I get this error message:

Windows Boot Manager
Windows has encountered a problem communicating with a device connected to your computer.

This error can be caused by unplugging a removable storage device such as an external USB drive while the device is in use, or by faulty hardware such as a hard drive or CD-ROM drive that is failing. Make sure any removable storage is properly connected and the restart your computer.

If you continue to receive this error message, contact the hardware manufacturer.

Status: 0xc00000e9
Info: An unexpected I/O error has occurred.

Oh and when i put the installation disc in when in windows it just gets stuck on copying temporary windows files...

System specs:

Intel Q9300
4GB 1066Mhz Corsair Dominator Ram
4870 512Mb
Asus P5K Motherboard
The HDD is a Western Digital 320GB drive

I built this system probably closing on 4 years ago now.

So before I go and splash out on a new Hard Drive.. Do you guys think that this is all consistent with Hard Drive failure or is there something else I'm missing?

Sorry for the long post! Thanks in advance.

[jordguitar]

Apparently it is a bios problem. If anything is plugged in sans keyboard or mouse unplug it and see if it works. Otherwise i dono. checking the hard drives smart wouldnt hurt either