The Commodore VIC-20 sold very well in the early 80s until it was replaced by the Commodore 64. The machine was very cheap and had cheap hardware, most cassette games required the expensive 16Ko add-on.
VICE (Versatile Commodore Emulator) is the best choice to emulate a VIC-20 on Windows, Mac and Linux. Not much choice, as all other emulators or
fork of the original VICE emulator, are now merged in the current VICE program. You can still find some old emulator for DOS or Windows on the web.
Running VIC-20 games in VICE
VICE allows you to emulate almost all Commodore computer. For the VIC-20, you have to launch xvic.exe. Try then to autostart disk/tape image as shown below.