You can't period. I'm betting you are thinking of using a VelociRaptor drive, but the problem is it draws way more voltage than a notebook sata drive usually does (it may be 2.5 inch form factor, but that is for performance, not for notebook size). Also, the drive itself probably won't fit in your notebook: while the platter is 2.5 inches, the physical casing of the drive will be to big to make it into a notebook.
Nope. The power connector, while physically the same, is hooked up differently. The desktop drive uses a combination of 3.3V, 5V, and 12V, while a notebook drive doesn't use the 12V, relying entirely on the 3.3V and 5V. The connector is the same for compatibility reasons (you can hook a notebook SATA drive straight to a desktop connector and it will work fine), but a desktop drive will not work in a notebook due to the lack of a 12V feed from the notebook.
I recommend going with a WD scorpio black lappy drive if you're interested in performance. I upgraded to one and it receives a 5.9 windows experience in vista and in win7. A significant increase from the hitachi drive that came with it.