Row Size changes with changes in Screen Display Settings

Background Info
Excel 2010
MS Windows 7 Enterprise
Monitor Resolution 1600 X 900

The attached workbook is a 2 page extract of a photo report. In practice, such report would comprise of several pages (typically between 30 to 50, depends on the number of photos in the report). The template is designed to have 2 photos on each page, with a photo number and description under each image. The remaining rows are blank, just to provide spacing; and this comes to a round 10 rows per A4 page. The report is populated by a macro that inserts these images from a directory location and copies description text from elsewhere in the workbook. The macro resizes the image height to match the row height, the image width is changes automatically as it maintains the aspect ratio.


Observations
When I change the screen display settings under Control Panel\Appearance and Personalization\Display, I observe:

1. Smaller 100% (Default)
   Excel shows that the row height is 8.47 cms / 240 points / 320 pixels, depending on the view (Normal / Page Layout / Page Break Preview).
   When I print this on an A4 page (No Scaling, 100% of the original), the actual row/image height is only ~ 8.2 cms.
   It fits the 2 photos. 10 rows to a page neatly as is the intended purpose of the template.
   
2. Medium 125%
   Excel shows that the row height is 8.47 cms / 240 points / 400 pixels.
   When I print this on an A4 page (No Scaling, 100% of the original), the actual row/image height is ~ 8.5 cms.
   It no more fits the 2 photos, 10 rows to a page.
   
3. Larger 150%
   Excel shows that the row height is 8.47 cms / 240 points / 480 pixels.
   When I print this on an A4 page (No Scaling, 100% of the original), the actual row/image height is ~ 8.5 cms.
   It no more fits the 2 photos, 10 rows to a page.

The 3 different display outcomes can be seen in the attached PDF files. I've also tried this with another monitor (screen resolution 1920 X 1080), but the results remain unchanged.

Issue
This report moves back & forth between a few users who prepare, review and verify it. They have different display preferences. How do I ensure that the row / image height remains unchanged, and the that the final report prints nicely, with 2 photos to a page as can be seen in the Smaller 100% PDF.

As a follow up, I'd like to learn what is the unit of measurement to determine/record Row Height in Excel?

Has someone come across something similar with Row Heights / Column Widths? Pls share your experience.