When the cursor hovers over a .jpg file, a popup displays information regarding the file. One of those attributes is "Dimension" which is displayed in pixels. How can I chage this to display the dimensions from pixels to inches?
The pixel dimension tells you how much information is in the file in terms of how finely grained the picture is. It is up to you what size you eventually print it out. This is dependent upon what picture viewing software you use and what options it gives you for printing, e.g. full page, fit width, etc. etc.
The other use for this information is to see whether the picture will fit without adjustment on a screen or in a web page.