Disable columns in a tabular form on select list

Question

I am trying to void out or disable certain columns based on the option value selected from the select list. I have done this on a form with regualr page items. However, I am now trying to accomplish the same on a tabular form. I have tried the following function and onChange event but it doesn't seem to be working. Any idea what could be wrong?
var htmldb_delete_message='"DELETE_CONFIRM_MSG"';
function Disable()
var sel = document.getElementById('f08_0001');
if (sel.options[sel.selectedIndex].value != '5' || sel.options[sel.selectedIndex].value != '7') {
document.getElementById("f04_0000").readOnly = true;
document.getElementById("f05_0000").readOnly = true;
} else {
document.getElementById("f04_0000").readOnly = false;
document.getElementById("f05_0000").readOnly = false;
THe onChange event : onChange="Disable()"

Answer 1

I've even gone ahead and tried th following code but still am having no luck
function Disable(pThis)
var currIndex = $('select[name="'+pThis.name+'"]').index(pThis);
if (pThis.value=='2') {
$('select[name="f04"]')[currIndex].disabled=true;
} else {
$('select[name="f04"]')[currIndex].disabled=false;
}