You have to delete de .sim file of the snes emulator (I think it's snes.sim) that you'll find in the GAME folder of the internal memory of your Dingoo, then copy an emulator (like Lion_rsm's one). You should have a new .sim, it doesn't really matter what name it has, but it has to be a .sim and you can't have to .sim emulators for the same console.
If you can't run games after that, search on the Dingoo's main screen for an option called "Update Jukebox". It searches for .sim emulators and updates the file association so you can run them.
There are also some emulators with .app extensions, like PocketSNES, but with the above you can do a lot.