Man you thinking and sacrificing too much about it, Oblivion is special for me because of its nostalgic value, but if you want to experience it for the first time you need a mod to really makes it seems not dated too much. Even that there are so many flaw in Oblivion that is alright and cool at that time but somewhat awkward today, it suppose to makes you laugh. I'm afraid your struggle is not worth it.
However unmodded oblivion is fine, I play it in many platform across the years, I don't know how many years pass already, how many PC and laptops I use, it is fine. Just download the Mod manager, no need the complicated one like wrye bash and install unofficial oblivion patch and other unofficial patch, it is not a mod it is essential, you cannot play without it, after that your game should be fine, if that also not work just play other game, if you have to put lots of serious effort, put it on a more serious and good quality game. Have you ever play Warband? try that game, it's awesome, and the mod mostly stand alone and very easy to install.