Where to place Bitcoin bootstrap.dat
From what you said, I'm assuming you're using an option like this when you run Bitcoin Core (bitcoin-qt):

-datadir=D:\BitCoinData


(if not, you should do something like that to specify that the blockchain will be on your 1TB HDD; otherwise, it's only the small client, and not the large and oft-updated blockchain, that resides on your HDD)

In this example, you would move bootstrap.dat to D:\BitCoinData\bootstrap.dat. Move the file there while Bitcoin Core is turned off. Next time you start Bitcoin Core, it will verify and use this file to build its databases before synchronizing the remainder over the network.