Halloween Harry is a little known, but very classy, platform game release in the hay day of DOS gaming. Smooth graphics, wide variety of weapons and lame story line (save the world from Zombie aliens) are all present.
In order to run Halloween Harry under Virtual PC you simply need to *not* enable the sound blaster. If you turn on the sound blaster the entire game will lock up – but if you stick with PC speaker if will play fine:
You can download this game from here: http://www.dosgamesarchive.com/download/game/90 if you want to give it a go.