Windows 7 Do I need to reinstall OS after upgrading my HDD?

[Jaxx89]

I currently have 3 SATA drives. 1.5TB x2 and 1TB x1
Drive partitions as following:
C: 499GB
D: 897GB
E: 499GB
F: 897GB
G: 931GB
I am installing a new 2TB SATA 3 drive, but on SATA 2 mode for now.
New config of drives will be quite similar except for that I will be merging the partition of the current drive which has the OS (C: & D 499GB + 897GB
The new 2 TB drive will have 2 partitions C: 499GB and the rest D:
The other drives will remain the same.

SO for this purpose, will I need to reinstall my OS
OR
I can transfer my Current one to my new drive (backup and restore OR third party software)
OR
I can use the System Image of Windows 7 I had created a while ago just in case my OS went corrupt.

I'm kinda confused and that's why I asked this question.
I'm buying a Seagate drive so can I use

DiscWizard​

EDIT: USERS WHO THINK I'M STUPID TO INSTALL 4 INTERNALS AS SATA AND NO RAID OR SSD, YOUR COMMENTS ARE NOT WELCOME.​

 

[cybercore]

SO for this purpose, will I need to reinstall my OS
OR
I can transfer my Current one to my new drive (backup and restore OR third party software)
OR
I can use the System Image of Windows 7 I had created a while ago just in case my OS went corrupt.

Backup is a good idea. With the help of third party tools you can extend system partition without loosing data and keeping the mbr in working order.

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