All About The Macintoshes: https://infinitemac.org/
Infinite mac is site for emulating old versions of Mac OS, going from Mac OS 1.0 to Mac OS X 10.4. It also comes prebundled with some games to play with (Some great examples being Doom, Specter, Glider and Another World.) And if that isn't enough for you, you could get even more games as it is connected to the software repository, the Macintosh Garden (Another good site.)
