Gorilla.bas under Virtual PC
Gorilla.bas is a BASIC game that shipped with MS-DOS 5, Windows 95 and a couple of other OSes (interestingly it was not included in MS-DOS 6 or 6.22). The game actually shipped as a source (.bas) file that you needed to load and run with QBasic. Gorilla is a fairly basic artillery game, where two players control large Gorillas that then throw explosive bananas at each other.
On each turn you get to specify the angle and velocity for your throw, with the winner being the first one to make a direct hit on their opponent. To complicate the game a little there was a random 'wind factor' that would affect your throws.
Gorilla runs just fine under Virtual PC:
One of the reasons I loved this game is that by having access to the source it was easy to tweak. I remember changing the size of the explosion generated by the bananas, and swapping the graphics resources so that you had two bananas throwing explosive gorillas at each other.