The ZX Spectrum has been very popular, with more than 5 million units sold in a 10 years span. Emulating the machine is quite easy.
ZX Spectrum emulators
A good emulator for Windows and Linux is Speccy, another great emulator made by Marat Fayzullin. Some ROM made not work very well, you should install
alternatives softwares, like NO$ZX, or EightyOne. Beware, EightyOne is
primarily made to emulate the ZX81, you’ll have to tweak the hardware options to emulate the Spectrum.
Running ZX Spectrum Games in Speccy
Speccy is really simple to use and most of the time will configure itself to emulate the best Spectrum model for a given game archive. In the following video, we run World Championship Manager immediately.