To complement teh cursor tolerance that affects grabbing, I added another option, drag tolerance. Currently it only affects mouse drags in selector. Any mouse drag which is smaller than the tolerance (in screen pixels) is ignored and is interpreted as a click. To me, this makes it much easier to select objects with mouse and especially tablet, as well as switching handles from scale to rotation, by eliminating the small accidental object drags that are very annoying.
The default value for this option is 4 pixels. Please test the latest CVS and report if you like the change, and if so, what value is the best for you. There's no UI for changing the value yet but you can edit it in preferences.xml:
<group id="dragtolerance" value="4.0"/>
and then restart Inkscape.
By the way I also wrote most of the HandlingPreferences tutorial on Wiki.