korell: The GOG versions of Arena and Daggerfall are the latest official versions, so in that sense you are better off getting the versions that come with all the unofficial community fixes and patches pre-installed. Here are the links:
[url=http://wiwiki.wiwiland.net/index.php?title=Arena_:_ArenaSetup_EN]http://wiwiki.wiwiland.net/index.php?title=Arena_:_ArenaSetup_EN[/url]
and
[url=http://wiwiki.wiwiland.net/index.php/Daggerfall_:_DaggerfallSetup_EN]http://wiwiki.wiwiland.net/index.php/Daggerfall_:_DaggerfallSetup_EN[/url]
If you really want the GOG versions, though, you can buy any one of the Bethesda games, so Redguard, Battlespire, Doom, Quake, Fallout, etc.
I now own Morrowind three times. First was on original Xbox and I gave up trying as the load times were horrendous. Then I got it on Steam recently along with Oblivion and Skyrim, but the only one I've played any of so far is Skyrim. Now I have it on GOG and this is the best version I own as it is a standalone installer that is DRM free and there's a friendly community that advised me on the best way to apply community fixes and mods to get the best out of it without changing it too much.
Don't forget the official plugins from the elder scrolls site, like the propylon index =)