1TB hdd's are great for the sheer amount of storage space in a small format but they are pretty much all 5400rpm. Not designed for speed at all. If your laptop offers the capacity for dual hdd's what I'd recommend is a fast SSD for boot up/games and the 1TB HDD for data and less frequently used programs or those that derive no benefit from fast HDD access
I TB (one terabyte) is the largest capacity hard drive currently available that can be used in most laptops. The high capacity will let you store lots of pictures, music, videos or saved games but doesn't necessarily tell us how quick it would be.