Don't be sad, you can patch it to work as windows 95 version and then use KeeperFX with it.
How to patch the game to obtain the D3D\win95 version:
download this http://www.tapper-ware.net/files/dk95.exe (self-extracting 7z archive)
it includes keepd3d.exe (directx executable) and keeper95 (win95 version), and also the executables for Deeper Dungeons.
Don't forget to update the CFG file with the correct path if needed.
Playing with KeeperFX
KeeperFX is an awesome mod that inject a new directx renderer via a DLL.
You can grab it from here: http://keeper.lubie.org/html/dk_keeperfx.php
modifying the .cfg file you'll be able to pimp your resolution up to ginormous sizes, just look at my version of Dungeon Keeper here, running at 1920x1080: