I think the people that absolutely love Morrowind got it earlier on. My problem was I had to get in on the original xbox about 2 years ago. So its like, I never got to use the mods and fix the bugs. That and it was on the original xbox.
Most people did get it years ago, but I've also seen several people on this forum who got Morrowind after Oblivion but still found it more compelling. Then again, it's all about personal preference. Some people who got Morrowind when it came out still prefer Oblivion to this day.
To the OP, if graphics are a deal breaker for you then get Morrowind on the PC. There are several projects out there that make the game look almost as good as Oblivion. As for whether or not you should go back and play the earlier games, you don't have to. Some parts of the lore won't make as much sense if you haven't experienced them first hand, but it's not necessary to your enjoyment to go back and play any of the earlier games. It's recommended though, since all of them are very good.