How do I disable click-drag-click behavior in blender? I am used to moving things with "click-drag-release" (holding down the mouse button and releasing it at the desired location).

How can I get Blender to emulate that kind of behavior? 

(right now i have to click, then move, then click again) I wish to instead just hold down the mouse button.
Go to User preferences, open Input tab, find 3D View > 3D View (Global) rollout.

Now scroll almost all the way down, until you find Translate (the one that uses tweak as a key-binding instead of keyboard).
Open that rollout and enable Confirm on release checkbox.