If the old drive is SATA, then any new SATA drive should work fine regardless of which version it is. Each SATA version is backwards compatible with the earlier ones, and for a laptop hard drive even the oldest SATA version is more than fast enough to keep up with the speed of the drive.
The only thing to watch out for is the physical size. For example, the very latest WD 1TB drives are taller than a "standard" laptop drive and probably won't fit into most laptops.
Youll more then likely need a 2.5inch drive, as sminlal touched on, instead of the more convential 3.5" desktop drives.
And as already said by sminlal, either works fine, and wont be bottlenecked at all, even desktop mechanical drives dont saturate Sata 1.5gb bandwidth...