[QUOTE=signit98;4318671]Bill, a new HD is less than $100 (for a decent sized one) and you can put it in in 15 minutes... installing the OS will be another 20 or so and you are going to be good to go!
Bill,
Signit98 is right on with his advice. A HD can go bad in a Mac or PC. But it is easy to install and format a new drive on a Mac.
Here are some links for Mac friendly HD suppliers.
http://www.macsales.com/
or
http://www.ifixit.com/
If you need any other help or questions, shoot me a PM.
regards,
Robert