Did you actually open the app? There are other emulators but I'm in no hurry just now. I have uninstalled BlueStacks.
The d/l'ed .dmg opened as a disk image containing an installer app, and I launched the installer, but I quit it at the point at which it asked me to click to install, so, not having installed the app, I couldn't actually open it.
There was really nothing to uninstall: Just quit the disk image and trash the .dmg.
And happy holidays to you, too.
