You script paint by selecting a script and painting strokes on the surface with the Paint Scripts Tool.
(Windows) Drive:\Documents and Settings\username\My Documents\maya\2009\scripts
(Linux) ~username/maya/2009/scripts
(Mac OS X) /Users/username/Library/Preferences/Autodesk/maya/2009/scripts
(Mac OS X) /Applications/Autodesk/maya2009/Maya.app/Contents/scripts/paintEffects
(Windows and Linux) mayapath/scripts/paintEffects
You do not need to move them to your personal scripts directory, however, any new scripts you create should be stored there.
For example, for the sample scripts type geometryPaint, spherePaint, or emitterPaint.
A script window may open, depending on the script. Entries may also appear in the boxes in the Setup section. These are MEL procedures and come from the script. You do not need to modify them. For more information on these procedures, see Script Paint MEL procedures.