Ok I have been playing Oblivion fine for at least 2 years off of Steam. Now I use a bunch of mod's and the game has worked fine for the past 2 months and I haven't installed any mods at all in that time. However today when trying to launch oblivion from steam I encountered a problem.

I get the mini menu that pops up as normal when you first load oblivion and that works fine the music plays and all. I hit "play" and heres where the problem begins.

It's hard to explain my problem but I will try my best.

So after I hit play the loading seems to be happening and everything but in the background since for some reason I'm still on my desktop. I can hit enter right away even though I'm on my desktop and it goes to the in game menu because I hear the menu music playing.. but on my screen I'm on my desk top...

So I try hitting ctrl+alt+delete to get to my task manager. I click the oblivion application and hit "switch to" but IM STILL ON MY DESKTOP! My computer thinks I'm in game apparently but there is no game screen it's just my desktop with the mouse pointer disappeared. I'm clueless of how to fix this. I restarted my computer and that didn't work. The problem only seemed to start today.

I searched google and could not find anyone with a similar problem. So here I come to the forums with a desperate plea for help!

My specs:

Intel R Core duo i7 @ 3.4 GHz
10 GB ram
NVIDIEA GeForce GTX 550 ti

I don't think my specs are the issue. I have been playing this game fine for the past 2 months with no issue until today. I also did not install any mods recently or change any files at all in the past few weeks or today.