Hello again!
I’m afraid that this time I cannot fully understand what you mean, because if you look at your own photo, for example this one
http://www.pbase.com/bostonrott/image/119939829it seem to me it gets open exactly like the one you mentioned
http://www.pbase.com/shy_cohen/image/121087434The code in green you copied has absolutely nothing to do with the image display.
What gives the appearance to the page with an image display is the CSS, you can choose if you want any border, or table background, colours and so on, but you cannot change the size of the image which is related to the original you uploaded.
It means that if you uploaded a very large picture, and you select to see it in original size, it will fill all your screen and you’ll have to scroll either horizontally or vertically to see it.
If you uploaded a very small picture, you won’t see it bigger than the original you uploaded in any way.
Usually PBase recognizes as standard dimension a picture which has as maximum size 800px, it means that if you upload a picture which is of that dimension ( 800px for the longest side) the original will coincide with the large size.
I apologize for my incorrect way to use English which is not my mother tongue, in my explanations and I trust you can guess what I mean.
If you wish to get the part of CSS code which controls the Image display section, I’ll be glad to give it to you.
Let me know.
All the best
Marisa