Reposted: Drop-downs & Iframes

[wxdqz]

Sorry if anybody actually got to reply to my original post (I think I deleted it fast enough), but my problem's changed.

Anyways, I'm trying to use Javascripting with Drop-Down menus to load the links into an Iframe contained on the same page as the Drop-Down menus. I seem to be getting an error within the bolded line of my scripting, but I can't figure out what it is.

<SCRIPT LANGUAGE="JavaScript">
function LinkUp()
{
var number = document.DropDown.DDlinks.selectedIndex;
location.href = document.DropDown.DDlinks.options[number].value;
}
function acrossFrames()
{
if (document.DropDown.DDlinks.options[0].selected)
frames[0].location='cotd.html'
if (document.DropDown.DDlinks.options[1].selected)
parent.frames[0].location='cotw.html'
}
</SCRIPT>

And here is the form:
<FORM NAME="DropDown">
<SELECT NAME="DDlinks" onChange="LinkUp(this.form)">
<OPTION SELECTED> --> Pick One <--
<OPTION>Script Tip One
<OPTION>Script Tip Two
<OPTION>Script Tip Three
</SELECT>
<INPUT TYPE="HIDDEN" onClick="acrossFrames()">
</FORM>

I got all of the code from HTMLGoodies.com's "Script Tips" from appx. week 40 (I don't have the exact address anymore).

Again, I am grateful for any help. Thanks.