(1.) Disable any floppy drive controllers present in your BIOS
(2.) Make sure Windows isn't designating your main interface as your default Windows sound device.
(3.) Nowhere NEAR enough info about your system, other than I only see you mentioning one hard drive.
IMPORTANT! You MUST use a secondary hard drive (not your main OS drive) for recording and playback of audio in Pro Tools. Recording or playback from the OS drive is known to be problematic and the cause of many different error types. If you are using your system drive and encountering errors, the first thing you should do is get a compatible drive.
Pro Tools supports recording and playback to a secondary drive that meets the following requirements:
- 7200 rpm or faster
- 9ms seek time or faster
But most importantly:
http://duc.avid.com/showthread.php?t=300050