That one can be fixed by doing - as root: "gtk-update-icon-cache -f /usr/share/icons/hicolor" A program you were most likely installing would have been running that above command and failed. Hence losing the spinning dots.
The most common cause for it to fail is lack of space. The JFFS2 filesystem used on the internal flash of your tablet wants as much space as possible. Which may explain your slowness, especially around updating packages and installing things as that will do a lot of writing to the flash.