I've tried putting script in an ascxand I get no dice.

<script runat="server">
Dim myString
myString =  join(PortalSettings.DesktopTabs(), ",")
</script>

I know desktopTabs is a function, I see the parantheses.  I just figured if I post incorrect code, I'll have more luck getting an answer to my question:

Where is the DNN menu array?

What is the property, variable, array, etc, called?
How do I convert it to a string variable in the skin file?

What you're looking for doesn't exist until the Menu skin object creates them from the database on a page request.  Maybe if you told us why you thought you needed this information.

Jeff