I wonder if we should split off some parts of this thread to something like "What was my 1st encounter with an Elder Scrolls Game?".
Nevertheless, here´s my story: I got Morrowind as part of a games compilation I mainly bought because of a Tomb Raider game and the excellent "Sub Culture" submarine sim. O.K., it was a very rainy sunday in my summer vacation and I did not feel like building another Star Wars model, so why not install this strange game with the mellow name? O.K., done. 1st start, then the opening with the goddess speaking to my char and then - pow! - the incredible voice of Jiub and stumbling thru the lower deck of the prison ship into the light of a misty Seyda Neen day. WHOW! 1st time hearing the Silt Strider and going thru character creation (1st of many, many times! ) Taking all the stuff I could get from the census office and stumbling out into the open space of Seyda Neen, selling all my loot at Arille´s tradehouse. 1st time waiting on the top gallery of the lighthouse to see that little elf hiding his ring and so on. Exploring the hinterland of Seyda Neen and getting the goose bumps as that magician dropped from the sky with an ear piercing cry. Quite soon afterwards my char got killed the 1st time by an aerial rat (cliffracer!). And so on.
A few hours later I returned back into real life, wondering where that afternoon had gone. I was completely hooked.
At Christmas that year I installed Morrowinter and I could spend very enjoyable hours having my char roam the area around Seyda Neen and Pelagiad with Bree, later Vilja, admiring the countryside.
Back to atmospheric mods: Besides Lokken I remember the famous "The Glory Road", especially that dream island of SolaLuna and in Oblivion "Claudias Little Secret". CLS was heavily over-sexed, but it had some incredibly atmospheric scenarios like that amazonian village with the floating spores.