Click the Style Manager Mouse control.
Select the settings you want:
Handedness: Reverses mouse buttons 1 and 3.
Button 2: Determines whether the middle mouse button is used to extend selections (Adjust) or drag-and-drop objects (Transfer). If Adjust is selected, transfer actions (drag) will require the use of mouse button 1.
Double-Click: Determines the maximum time between clicks of a double-click. (Test the speed by double-clicking in the mouse picture provided.) A new double-click speed does not take effect until the next time you log in.
Acceleration: Sets how fast the mouse pointer moves across the display.
Threshold: The distance in pixels the pointer moves at a slow speed before moving at the accelerated rate.
To save the changes, click OK. To return to the default settings, click Default.
You can also set the edge Move Threshold (the minimum proximity of the mouse pointer to an object without the object becoming selectable) for the mouse. See the dtwm man page.