SATA HDD Borked?

Hello all, hope someone can help me here. My computer has been well and truly fucked for no good reason, hence why I wasn’t about for the EB2L game. It all started when I shut my computer down after doing nothing but let Tess check her Ebay purchases (no installing, fucking about with registries, etc.) and the next time I booted up I got stuck on the Windows XP splash screen with the little blue bar looping indefinitely. After much swearing and huffing I got around to unplugging every periphery but my monitor with no luck, disconnecting my DVD and CD drives and nothing, then taking out all my PCI cards and reseating them, leaving out the ones I didn’t need. None of it was helpful until I got to the last thing it could be without it being my Windows drive, my SATA HDD, used just for storage and games, and bingo! Booted up no problem. This is a bit of a double-edged sword though, and whilst I’m glad to have my computer back online the thought of my HDD being borked and the idea of having to spend money to get another one is rather galling. If I boot up windows and then plug the SATA HDD in the whole computer freezes up, which leads me to believe that the thing is irretrievably buggered. My question is this: Is it shafted beyond repair and should I go out and get a new HDD, or is there hope?