Form submission

On my form at www.meadowlarkco.com/payment.htm

How do I make it so that the enter key is disabled…I’ve added

<script type=“text/javascript”>

function stopRKey(evt) {
var evt = (evt) ? evt : ((event) ? event : null);
var node = (evt.target) ? evt.target : ((evt.srcElement) ? evt.srcElement : null);
if ((evt.keyCode == 13) && (node.type==“text”)) {return false;}
}

document.onkeypress = stopRKey;

</script>

to the head tag of my html page

It appears to work, what’s the problem?