How long does it hang for? I've had drives that stop as certain places for 20+ minutes and then eventually works out what it's doing and continues. If it hangs for over a couple hours on a slow computer or 30 minutes on a fast computer then I would lean towards a failing drive.
Thanks for the answer guys. My problem has been resolved. Basically what happened was that I was trying to format the drive, however I was doing it under Windows Vista 32-bit, which apparently doesn't recognize a drive that big unless you're doing it under a 64-bit operating system like Windows 7. I had Windows 7 64-bit ready to go and under that I had no problems.