Seen multiple threads around about this issue and have experienced it myself on multiple PCs.
When minimizing the main Workstation window the window minimizes for a split second, then reappears, clicking minimize again just causes the same action. The only option I can find is to resize the window and hit Windows+D or Alt Tab out.
That this has not been fixed despite numerous updates is ridiculous. And VMWare wonder why people aren't buying it...
When will this be fixed?