Senza le lungaggini di jQuery....

codice:
<!doctype html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
<title>Esempio</title>
<script type="text/javascript">
function chbSum () {
	var oDisplay = document.querySelector("#totale");
	oDisplay.innerHTML = parseFloat(oDisplay.innerHTML) + (this.checked ? parseFloat(this.value) : - parseFloat(this.value));
}

window.onload = function () {
	Array.prototype.forEach.call(document.querySelectorAll(".chkOptions"), function (oChB) {
		if (oChB.checked) { this.innerHTML = parseFloat(this.innerHTML) + parseFloat(oChB.value); }
		oChB.onchange = chbSum;
	}, document.querySelector("#totale"));
};
</script>
</head>
<body>
<form name="tuoForm">
	<div id="totale">200.50</div>
	<h3>Opzioni</h3>
	<input name="checkbox[1]" class="chkOptions" value="10.00" type="checkbox" id="1">
	<input name="checkbox[2]" class="chkOptions" value="15.00" type="checkbox" id="2">
	<input name="checkbox[3]" class="chkOptions" value="20.00" type="checkbox" id="3">
	<input name="checkbox[4]" class="chkOptions" value="25.00" type="checkbox" id="4">
</form>
</body>
</html>
P.S. Ho presupposto che questo comportamento debba essere valido per tutte le checkbox con class="chkOptions". Gestiscitelo di conseguenza...