My computer cannot boot. Start up repair does not work. It fails and displays the following:

Event Name: StartupRepairOffline
Prop Signature 1: 6.1.7600.16385
Prob Signature 2: 6.1.7600.16385 
Prop Signature 3: unknown
Prop Signature 4: -1
Prop Signature 5: Autofailover
Prob Signature 6: 4
Prop Signature 7: CorruptRegistry
OS Version: 6.1.7600.2.0.0.256.1
Locale ID: 1033

The latest (and only) system recovery date was from the day before, the day it turned off never to return. When I attempt a system recovery I receive the message "System Restore failed while mounting the registry from the restore point. The registry in the restore point was damaged and could not be restored." No previous restore points exist on the list. 

So I ran Preboot System Assessment and it was all clear until it got to the HDD, at which point I received error code 2000-0142. I looked up the error code and amongst the hundreds of error code solutions on the Dell website, the solution for mine was "check your warranty/check our selection of new hard drives!"

My hdd is a 3.5" sata (SATA:ST3750528AS). I have accepted that it is a failing/dead hard drive, but I need help deciding how to deal with the situation. 
 

Would buying a hdd enclosure and accessing it through another computer work despite the 2000-0142 failure?
or
Would buying a SATA-to-usb 2.0 adapter be better suited for accessing my dying/dead drive?

I realize that people often pay lots off money to have experts do a data recovery and that there is no guaranteeing success and there is no refund upon failure (ridiculous, it is result-based service, not a labor-based project). I will buy any equipment that is necessary to save my data, but I am hesitant to waste my money being a noob and end up with useless hdd accessories. Please, is my drive salvageable? Does it sound I am on the right track to recovering my data or will I end up having to pa a professional?

I patiently await your replies. Thank you for reading this far and thank you even more for any help or feedback.

-Bill

 moved to the disk drives forum by natakuc4