This is what I did;
Install game normally,
Patch the game to the latest version (1.70 I think). If it crashes a lot while playing, you can try the more stable 1.6 patch (it was something like 1.6 don't remember).
Right click Dungeon Keeper2 shortcut and set compatibility mode to Windows2000 (others don't work).
Did you try these things?
By the way DosBox is worthless for Windows applications.