Sorry for the delay, wanted to give this a proper test.
I was able to get a 8.1 Virtual Machine to automatically login using that method. It didn't work the first time though.
When I unchecked the box and pressed OK it prompted for username/password for automatic login. The username that was filled out was wrong, and I had to write out my full account name (in my case, using a @hotmail address) and of course the password. My first attempt had me enter the wrong password, so when I rebooted it didn't login automatically- but it did start off saying that the login password was incorrect. Once I repeated the steps and entered the correct password, it now logs in automatically for me when I reboot it.
To uninstall an app you should be able to right-click it, Uninstall should be one of the menu options.
