The washer filled just fine, but it did not complete the wash cycle (it's still full of water and soap). An awful smell of burning rubber came from the machine after it stopped. Is there an obvious thing that we should check first? Should we check the drive belt? Also, is there any reason, if we can move the thing, why we should empty it before working on it?

Thanks!

You need to find out what is stopping the drive belt from turning or what is causing the drag on the drive belt to start with. Then replace the ofending part along with a new belt.