You have to use software to "clone" the old drive to the new drive. Most HDD manufacturers provide free cloning software on their support websites. You will likely need to re-partition the cloned drive to use it full capacity. For that, EaseUS offers some free for home use partitioning software that work on 32-bit and 64-bit systems on its website.
I have a 100gb windows partition on a 2tb WD hdd that i want to move onto a new 1tb seagate drive.... how can i do that with all the boot partitions intact?
In your situation, you could migrate your Windows system partition from your old hard drive to your new hard drive by using some partition software, and most free partition software (such as Partition Assistant Home Edition) integrates the feature “Partition clone”. You could download them from most download website such as CNET, etc..Here is a detail tutorial about “how to clone your system partition to another hard disk”. I think this feature could help you.
Note: To migrate the windows 7 OS, you need not only clone the system partition but also the “system reserved” partition.
Here I replenish some famous partition software:
open source software: Gparted
Free software: Partition Assistant, EaseUS Partition Master, Partition Wizard,
advanced software: Acronis Disk Director (this software maybe the most powerful partition software, unfortunately it is not a freeware, and the price may a little high)