DOSBox

To load the DOS games you must put the folder inside the /roms/pc subfolder and generate a text file with the name of the game with the extension .conf and inside the path to the specific game for example WOLF3D.conf and inside;

[autoexec]
@echo off
mount d "/home/pi/RetroPie/roms/pc/WOLF3D"
d:
WOLF3D.EXE

After search games on the OS an run from the list, remember you need keyboard and mouse for thi system.