http://www.seagate.com/ww/v/index.jsp?locale=en-US&name=SeaTools&vgnextoid=720bd20cacdec010VgnVCM100000dd04090aRCRD
Test your HDD. If ti fails the test remove it from this system fit it to another and retest.
If it still fails the Drive is faulty but if it passes the second Test the M'Board, Data Lead, Power Supply is faulty in the first computer and need attention as required.
As for your Data if the Drive is truly damaged and fails the Seatools Tests you should package it up and send it to your Preferred Data Recovery House and get them to recover your Data.
If you mess with this drive now and fail to get your Data off it you will increase the costs involved in doing a professional recovery and decrease the chances of having a successful recovery performed.
However if this data is just nice to have and isn't worth the $1,000.00 + involved for a Professional Recovery you can try a Data Recovery Application
Here is a short list of the better ones
http://tinyurl.com/273ay5
http://tinyurl.com/rmvrv
http://tinyurl.com/yvrsl
http://tinyurl.com/yyk8cm
http://tinyurl.com/382vm
http://tinyurl.com/ynwnel
http://tinyurl.com/nc4kx
http://tinyurl.com/2wox7l
http://tinyurl.com/374d8b
http://tinyurl.com/djw6u
http://tinyurl.com/f73se
http://tinyurl.com/8bd3f
http://tinyurl.com/afu2j
While the last 2 are from the same company they are very different products. Win Hex should only be considered foe use by someone who knows Hex Inside Out while Davory is a great cheap General Purpose Application.
Personally I prefer the On Track Option but it's anything but cheap. However because I use this type of software a lot it's paid for itself many times over by now, for a cheaper option Spin Rite from Gibson Research or Stella have both very good reputations by other TR members.
Col