<script language="Javascript">
 var initBody
 function beforePrint(){
  initBody = document.body.innerHTML;
  document.body.innerHTML = idPrint.innerHTML;
 }
 function afterPrint(){
  document.body.innerHTML = initBody;
 }
 function printArea() {
  window.print();
 }
 window.onbeforeprint = beforePrint;
 window.onafterprint = afterPrint;

 function printArea1(){
  if (flag == false){
  initBody = document.body.innerHTML;
  document.body.innerHTML = idPrint1.innerHTML;
  flag = true;
} else {
 document.body.innerHTML = initBody;
 flag = false;
}
}
</script>

프린트할 부분과 본문전환할 부분을 아래처럼 감싸줍니다.

<div id="idPrint1"> //본문전환
<div id="idPrint">  //프린트출력   
내용
</div>
</div> 

<input type=button border=0 align=absmiddle value="출력하기" onclick="printArea();">
<input type=button border=0 align=absmiddle value="본문전환" onclick="printArea1();">