6 yo Acer Aspire laptop can't boot due to sysconfig changed & disk err

I have an Acer Aspire 4736G laptop (6 yo ).

It was hit by ZeroAccess in 2013 but I managed to regain access using multiple tools from the WWW and reading other people postings who had the same predicaments like me.

All files and data recovered and backup to other media.

I used the system restore to restore to factory default with 90 percentile success with another 10 percentile using the factory backup restore DVD disc.

Started a fortnight ago, my laptop shutdown automatically even before booting into the password section.

A few days ago, I cannot boot into the password section where I typed my password to reach the Windows 7 area.The HDD ran on for 30 minutes in Starting Windows section until I pressed the radio button to switch it off.

Relaunched Win7 and boot into >F8> Startup Repair mode and the result was system config changed!>Finished>Shut down.

Next, I retried turning on and off the system to boot into Win7 using the radio button. Startup Repair reported disk errors.
Attempting repair and failed many times.
It even shutdown on its own when launching the Startup Repair Process.

The BIOS cannot save changes at all.Pressing F2 and F10 changed nothing.Cannot change
boot sequence from HDD to to DVD ROM.

I used Peppermint 3 Live disc to recover or backup my files, the system report SMART Disk Errors 52 bad sectors and now reallocating damaged data.

The folders where the files are kept cannot be accessed unlike in the past.

REATOGO XP had the same result.Tried using OTLPE to scan HDD, it reported not Windows 2000 or later platform.

Today I ran Startup Repair, attempting repairs successful.Files are all fine.
Did backup.
However, Not Responding is very frequent and laptop is very slow in responding.

Ran chkdsk,scandisk,sfc/scannow
All reported OK with 8KB of disk errors.
Even SMART reported WMIC Status OK

So what is the problem?
ZeroAccess in MBR partition?
ZeroAccess relapsed?
HDD failure?
What had happened to sysconfig changed reported in the first Startup Repair?

Thank you for any suggestions.

Easiest thing to start with is to check the HDD.

Run the DOS version of the LONG test of SeaTools, as described here:
SeaTools for DOS and Windows - How to Use

Run SeaTools as recommended.

Replace that disk as soon as you can.

Thank you very much for your advice,mate.
I already bought a new HDD yesterday but still using this one chugging on until it got busted! LOL!
Already backed up all files .