If we can count mods, Morrowind is still really good for a game so old.
Old 2D and isometric 3D games that were good are still good, detail level remains the same, but, for example in Planescape:Torment, patches that allow to use higher res on recent PCs and displays (I use a 1280x800 patch to play it at native resolution of my portable, that, despite more than 8 years old, is many times more powerful than the game's original recommended specs) make the games better playable and show larger parts of each level, making the games more pleasant to watch too.