Hi my name Ian - can you confirm that when you first start a program you can hear the drain pump spinning and trying to pump out the sump water or does it just hum ?
OK you have water in the dishwasher, if you put it onto a new program is that water pumped out?
OK the first thing you will have to do is to locate the pump, just follow the grey corrigated pipe, tip the appliance backwards and carefully take of the base and this gives you access into the bottom. Power off please. find the pump and take it off and see if you have a piece of glass bone etc stuck in there. Once you have this done come back to me. Remember you have water in the appliance and a bowl and towel may be needed.