OK, I'm two days old to KDE and Plasma. I have items in my Desktop folder, but they do not appear on my desktop. Can I place them on my desktop?

Right click on desktop -> Desktop Settings -> Layout: Folder View -> OK.
If it doesn't work, go back to Desktop Settings and change the location to your desktop folder in Location.

You can also add a single Folder View widget to your desktop. That way you can show several locations at once.

By the way, a tip for future posts: summarize the question in the title. A title like "Newbie Question" is very generic, it's more likely you'll get help from the people who know if you specify your problem.

Sorry about that. OK, in my Desktop Settings, the Layout option has only two items: desktop and newspaper. There is also no folder setting anywhere in the dialog.

You're probably missing a package. Try installing plasma-widget-folderview (you might want other "standard" widgets as well, not sure how the packages are named in Kubuntu. There should be a kdeplasma-addons with extra widgets).

OK, well we might be on to the cause of several problems, then. I installed the packages I THOUGHT I should from Ubuntu under Unity (and likely missed a few). Perhaps there is a more proper way to install KDE and Plasma?

Can you tell us which packages you installed? As far as I know there's a meta package for KDE in Kubuntu.

It's a good idea to install kubuntu-desktop to use KDE on ubuntu, it also adds some useless packages like splash screens, but ensures you have everything you need.

Well, I'm back. I installed the fresh mint KDE, and all is well. I tried the widget, and it worked. I also set the desktop to folder view, and that works. Thanks!