ScummVM is a free and open source software that allows you to run certain classic graphical point-and-click adventure games, only if you have their data files. In other words, it replaces the originally executables of the games, allowing you to play the games directly (without DOSBox like emulation) on new system.
Unlike DOSBox, ScummVM provides custom emulation for each game and not for DOS itself. Of course, this means ScummVM emulates games in an opt-in fashion. That is, the developers choose which games would be supported, as opposed to DOSBox in which you can (at least try) run anything that runs under DOS.
Since ScummVM uses the same license as DOSBox, almost as unintrusive in its installation (the general configuarion file must be put in one of Windows' special folders), and just as cross-platformed, once a game has (custom) support in the limited range of supported games in ScummVM, it is pointless to run it in DOSBox anymore.