2003 Evo 8, Clutch won't disengage
 

What's going on everybody.
I have a problem with my Evo 8. Soo i'll be driving and when i stop at a light and i down shift into neutral then i will shift into first without releasing the clutch and it dies??? So I start it back up and it won't idle properly so i have to rev it for like 15 secs then i'll try putting it back into first and it will die again. I hope someone can help me out or give me some ideas. It's at a shop now and he is telling me its my throw out bearing. I have got some other ideas from people i know saying it's a fuel pump or an o2 sensor. Let me know, please!!!\
Thanks.