Guild Wars 2

As stated above, my mouse cursor is acting like the windows key. Hit a skill with the mouse, game minimizes to desktop. Use the skills with number keys only, skills work as intended.
This started happening after purchasing HoT. Are other players also experiencing this?

I have never heard about an issue like this. Are you sure you aren’t hitting the taskbar accidentally somehow? At times, some window would stay above taskbar but any interaction would go to taskbar instead, I have seen it happening before. How are you running the game: full screen or windowed mode?

Does this happen even if you click on your character portrait at the character select screen, or anywhere else on your screen while in-game, or only when you click on the skill activation icons?

Possibly related:
Do you happen to have any overlay programs running that could cause your mouse click to switch focus to that program instead of staying on GW2?

If you are unsure, perhaps list what programs are running at the same time as you are playing GW2 to help see if any are a problem.