The Classic game Risk II running in Sheepshaver on my Lion Mac Mini:
[click on images to enlarge]
Here is a post I recently assembled for another similar question:
With the newer Intel Macs, you have to run a Classic emulator such as SheepShaver, which requires you to extract the Mac ROMs from your older Classic Mac and then install Mac OS 9.
A related program is Chubby Bunny, which comes bundled with all of that included (google the term "Classic-On-Intel v 4.0.1 chubby bunny").
More information on SheepShaver:
and more information about Chubby Bunny: