My xbox 360 won't turn on :(

Yes, you can get your Xbox 360 replaced since your 2 year plan is not up. Depending on where you bought it from, you should be able to take it back to the store where you got it and they can replace it for you. I did that with mine at Best Buy. Otherwise you can ship it back to Microsoft and they can ship you back a new one. the directions to do that are on Xbox.com
As for getting an Elite with your plan, I'm not sure whether you can do that. It's probably up to the store you bought it from, but i have no idea.
hope this helped!