window.onload = setNow;
function setNow(){
  var day =new Date();
  var yy = day.getYear();
  var yy = (yy< 2000) ? yy+1900 : yy;
  var mm = day.getMonth()+1;
  var dd = day.getDate();

document.getElementById('mon').options[mm-1].selected = true;
document.getElementById('theday').options[dd-1].selected = true;
document.getElementById('year').options[yy-2010].selected = true;
}

function do_url() {
<!-- baseURLのURLを管理画面で取得できるプラン一覧にセットする// -->
  var baseURL = "http://www.jhpds.net/oarai-hotel/uw/uwp3100/uww3101.do?yadNo=328561"
  var stayYear = document.F1.stayYear.value;
  var stayMonth = document.F1.stayMonth.value;
  var stayDay = document.F1.stayDay.value;
  var stayCount = document.F1.stayCount.value;
  var adultNum = document.F1.adultNum.value;
  var roomCount = document.F1.roomCount.value;
  var minPrice = "0";
  var maxPrice = "999999";
  var mealType = document.F1.mealType.value;
  var careNsmr = "";

  var listURL = baseURL
	+ "&stayYear=" + stayYear
	+ "&stayMonth=" + stayMonth
	+ "&stayDay=" + stayDay
	+ "&stayCount=" + stayCount 
	+ "&adultNum=" + adultNum
	+ "&roomCount=" + roomCount
	+ "&minPrice=" + minPrice
	+ "&maxPrice=" + maxPrice
	+ "&mealType=" + mealType
	+ "&careNsmr=" + careNsmr;

<!-- 同一ウィンドウ遷移の場合は残す// -->
  //document.location.href = listURL;
<!-- 別ウィンドウ遷移の場合は残す// -->
  window.open(listURL);
}