I have a page with several forms. I am trying to submit one of the forms (say form A) (NOT through Ajax, since I need to load the result page after the submit is processed)
Well, you have to copy the data from form2 to form1 before the submit. Here is the basic to get you started:
$.each ( $('#form2 input, #form2 select, #form2 textarea').serializeArray(), function ( i, obj ) {
  $('').prop( obj ).appendTo( $('#form1') );
} );
This function would select inputs from form2, get their current values, then create a new hidden input for each of them and add them to form1.
Depending on your scenario you may want to check the existance of input with same name on form1 first.