Seagate 500gb 7200.12 problem

Hi

I recently purchased a 500gb seagate 7200.12 which has worked fine untill today. Windows 7 froze while i was using internet explorer, i reset my system but it wouldnt boot up so i then removed my hard drives (except the bootable one). Started it up and booted fine so one by one i put the rest of them in and booted my system. My fourth sata drive wouldnt let windows boot!?! I noticed it was making a winding noise followed by a click, so unplugged fourth, booted windows then inserted the sata cable while windows was running. Windows recognises the disc, i then check for errors and bad sectors but all was fine. 5 minutes later windows crashes so i take the sata cable out the problem drive then all is fine!?!

Does anyone know how i can access my disc as i have really important stuff on it?
Ive looked for hardrive noises online but have found none that match mine, does it sound serious?

Any help/ideas/info much appreciated

Thanks
Ryan Whitelaw