The file you are downloading is a special package created by GamesNostalgia so that you can easily run this DOS game on Windows Vista, 7 and 10, without any additional effort. The archive includes the required emulator (DOSBox) and it's already configured. All you need to do is uncompress the ZIP or 7z file into your Games folder (e.g. C:\OldGames\), then open the folder of the Game, and double click the icon "Name of the Game" (it's a ".bat" file).
See the Help page for more info.
The creator of Maniac Mansion and Monkey Island