I finally did get Java working, it was just a matter of adding the right packages in Synaptic Package Manager (derp). Not sure which ones finally did the trick, lol, but I tested it and my screenshare works, so I can use this live usb for work, which was my original purpose.
I'm still a little fuzzy on the practical difference between a live usb with persistence and a full install - can you break it down for me in super-noob terms? I'm comfortable with computers in general and would consider myself a "power-user" in Windows, but I'm so new to Linux that I don't think I have a full context to grasp what you're saying.
Is it as simple as with a live usb the entire OS is running in RAM, whereas with a full install it will be running directly from the usb drive?? Again, thanks for your patience! This is a great forum, and at the risk of invoking Murphy's Law, I haven't once been yelled at to search, even though I'm sure this has been covered before. (I did search, just couldn't find an answer I could understand)
Also, what exactly is the difference between UNetBootin and Universal USB Installer? Or are they just different programs that do essentially the same thing?