Do I need to worry about my HDD & if so, what HDD of the ones listed below do you recommend?

I have Windows 7 Pro 64-bit with 8 GB DDR3 RAM on a Gigabyte motherboard.  

I also have:
1. a 7200 RPM Seagate SATA2 500GB HDD (16 MB cache),
2. a 7200 RPM 500 GB Western Digital SATA2 Caviar Blue (16 MB), and
3. a 5400 RPM 1 TB Western Digital SATA2 Caviar Green (64 MB cache) hard drive.

HDD 1 above is he OS drive.  HDD 2 above is for downloads and special projects.  HDD 3 above is the backup drive.

Recently, I had a HDD failure coupled with a backup failure, losing a lot of files in the process.  It was a Seagate drive (see https://www.experts-exchange.com/Networking/Network_Management/Disaster_Recovery/Q_25056767.html).

I replaced the old Seagate with HDD 1 above, which had been the backup drive.  Ever since I got this hard drive, I have been able to hear sounds coming from it, like crunching ball bearings.  I used the Seagate software (Seatools) and ran each of the tests offered. The HDD passes all tests.

I then used WD Data Lifeguard tools to check the HDD 1.  Strangely, it lists the HDD as an IDE, rather than SATA.  The HDD passes the SMART status, but any other test it fails.  In fact, all HDDs fail the WD tests, but pass the Seagate tests (error received for each HDD:  "Cable Test::Write sector error!").

My problem is this:  Windows 7 backup of the OS HDD occasionally fails (once or twice per week) due to the disk being corrupt, with the Action Center suggesting I run Chkdsk.  And each time I restart my computer, the chkdsk runs, corrects errors and then the backup is fine for a few more days.

The specific error associated with the failed backup as listed in the Event Viewer is:

Source: Ntfs, Event ID: 55, Task Category: (2), The file system structure on the disk is corrupt and unusable. Please run the chkdsk utility on the volume C:.

I have run chkdsk on the other HDDs, and chkdsk states that they are clean.

I also get the following error often:  Source: Disk, Event ID: 7, The device, \Device\Harddisk1\DR3, has a bad block.

I have included a couple really long images showing most of the errors listed in the Event Viewer.

My questions:
(1)      Do I need to get a new hard drive for the OS (HDD 1)?
(2)      If I do need to get a new HDD, would you recommend WD6400AARS, WD5001AALS, WD6401AALS or WD6400AARS (or any other) for the OS drive?
(3)      Lastly, what do I need to be able to transfer the image from HDD 1 to whatever new HDD I get (i.e., I do not want to be reinstalling Windows and all the software I have…it takes days to do so)?

Thank you,
edsager
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