data recovery - Help! Need To Recover Partitions

Ok, I will describe each & every step I performed.

First the problem:

A few days ago, my laptop refused to boot. It showed me automatic repair, but the repair was unable to solve the problem. So I checked the log file. The log file said that the bootloader was not found.

Since I was in a hurry for my work. I booted an Ubuntu live CD & tried to write the bootloader

I ran a command in ubuntu
Sudo dd if=/usr/syslinux/mbr.bin of=/dev/sda

What it did is make situations worse.

This command deleted my system_drv partition which was the boot partition.

So I ran testdisk & recovered that partition.

In testdisk I selected Intel type partitions for recovery.

Though the partition was recovered it wiped data from the rest of my partitions. Now in my laptop there is a LENOVO partition containing the lenovo drivers, SYSTEM_DRV (boot) & some other recovery partitions. Two partitions remain one was Data & other is Windows8_OS.

When I did my first recovery should I have selected efi/gpt instead of Intel? & if yes is it possible to recover now or I have lost my data?

My final questions are:

Should I try to recover those partitions using testdisk?
Or Is There Any Other Reliable Software?
Or Is There Any Alternate Way?
Or should I just handover to Lenovo for repairing the drive.

Though the data is gone I have checked in Gpart & confirmed that the partitions are still intact & I assume the partition table is also intact. The partitions still showup in Gpart but with an red exclamation & no used space just the size of the partition.

Please suggest a solution I am very worried coz my data is too important & want to restore my laptop as it was. Please I am in need of help.

Atlast I went to Lenovo Service Center for re-installing my OS. Which they did. I am not happy at all with the Lenovo Service Center at Impact Infotech Pvt. Ltd., Goregaon (East). While they did install my Operating System they deleted all partitions including the Lenovo partition which had the Drivers of my laptop, they don't have any knowledge regarding any issues related to an Operating System. Plus they charged me Rs. 800 for installing a pirated Operating System.

I recommend DO NOT GO TO THIS Lenovo Service center they will install a pirated OS on your laptop instead of installing from a recovery disc & laptops nowadays show "Media Test Failed" when they are switched from UEFI to Legacy Support. They will trick you that your Hard Disk is damaged & will charge you extra bucks for it.

Now I am having a working laptop with Windows 8.1 Pro which he installed.

Thanks to @oldfred for helping me solve my problem. I learned a great deal of knowledge from you. Keep up the good work.