Printing problems with original IPad
In trying to understand you question it looks like you have 2 problems.

1--Your Yahoo email is not printing, since it does not know where to print it..so check the settings for Yahoo email

2--It is difficult to understand what you mean by 


  When I print out of Photos, only the center one third of the page


Since you might have more the one print settings profiles set up (that is why Google email works) and others do not!

I would in any case check you print settings in the System Preferences and correct them.