The property which defines that position is called the origin. You can define the "origin" to be something other than (0, 0) dynamically in your program using the origin property in a property node. The following shipping example actually shows you how to use this property to change the origin:
C:\Program Files\National Instruments\LabVIEW 8.2\examples\picture\pictctl.llb\Picture Control - Zoom Attribute.vi
You can also find it in the Example Finder using Help -> Find Examples... in LabVIEW - click the search tab and search the keyword picture.