at same time i got the GOTY content for oblivion to work and now i dont know what to play 1st XD

Finish Oblivion's content first otherwise when you go back you just wont want to play anymore. Then move on to the land of Vvardenfell

Shivering Isles is probably the most immersive experiences I've had playing Oblivion. The isles are gorgeous (it's really cool at night) and the lord of the realm is my favorite NPC. It doesn't take too long to complete the main quest, and there are a few things worth mentioning but I think Morrowind takes a lot more time to get through so I'd play Oblivion first.

I say play Morrowind first. Do it in order. If you haven't already try out Arena and Daggerfall if you can handle the graphics that is.

Probably better if you start on Morrowind first. After playing through Oblivion, the combat system in Morrowind will probably feel strange and the game is harder. So yeah. :thumbsup:

Play Morrowind first, second and third.