Will my new Elite have problems?

How long do you think my new Xbox 360 Elite will last until it overheats? My temperature in my house is usually set to 77 degrees. How long? I'm getting it for christmas and i'm scared it will overheat when i play my modern warfare 2. I'll probobly be on a long time since everything is new. What are chances? Also, i usually have 4 bars but sometimes i'll have 3 bars or 2 with bad host.

My Download speed is 1.5mb and my upload is 256kbps. I know its sucky but its good enough. Will i have problems on Xbox with Modern Warfare 2?

well my 1st xbox pro 20gb(1st gen), lasted 4 years and it got rrod earlier this year I paid to get that fixed and then a few months lar my laser died out,so I bought a holiday bundle elite 120gb and the first day I got it, it had an e64 error...now im waiting for it to be shipped back to me by microsoft,it should be here by monday.