Alright, so I have some extra money here and I'm in the middle of deciding if I should spend it on a different game of the genre or spend it on Morrowind.

Now keep in mind I've put in years of play-time into Oblivion and the original TES games (Arena, etc.), however, I have yet to play Morrowind for some reason.
So is Morrowind really essential to the story-line/for building up to Skyrim or should I just buy a different game for once? What are you suggestions?

It isn't essential at all, but definitely worth trying if you haven't yet.