Hi, I have had this problem for a while now (about a month after I installed Windows 8.1 on my fresh new computer).
The issue is when I switch windows (the odds are much greater if I minimise or use the show desktop button in the bottom right), the program may not respond, and require to be forcefully closed in task manager (or spamming the X button) to close, then reopened.
This is not normal behaviour and is starting to get onto my nerves since I constantly have to restart my browser when switching between my IDE and it.
Just recently it has started closing a particular background program too (Logitech Gaming Software) which is why I am now contacting support to resolve this issue.
http://imgur.com/uVqpZwg
This is my step(s) to reproduce the issue.
I suspect this may have something to do with using an SSD and having a harddrive with my programs on. I modified the %programfiles% system variable and installed all new programs into that location.