If you clear the option "Show Windows Store apps on the taskbar" in the "Task Bar and Navigation properties" dialog you'll get rid of the "title bar" of store apps. (Right-click on the taskbar, choose "Properties".) You can also close an App with WindowsKey+DownArrow. See here[^] for more keyboard shortcuts. Also, the problem you describe with teamviewer has nothing to do with windows 8, this can occur (and has occurred to me) in windows 7.
If your actions inspire others to dream more, learn more, do more and become more, you are a leader.-John Q. Adams
You must accept one of two basic premises: Either we are alone in the universe, or we are not alone in the universe. And either way, the implications are staggering.-Wernher von Braun
Only two things are infinite, the universe and human stupidity, and I'm not sure about the former.-Albert Einstein