SPEC256 is very easy to use.
First, download the emulator from the downloads
Once in you hard disk, unzip it to a folder. You'll see that the zip will create a folder
for each game supported. Now choose a game in the download section. When the download
finishes, then unzip it in its folder.
by doubleclicking it. Spectrum start screen will appear.
Press F7 to choose the 256-color game and
F5 Load a normal game
F7 Load a 256-color game
F9 Change settings
Only currently supported games display 256 colours. The rest of the games will work
as with any other Spectrum emulator (Load it with F5).
See the readme.txt for more details.