Will monitoring company handle medical alerts?

Hi, we are in the beginning stages of trying to find a medical alert system that will allow my elderly mother to live alone but with some emergency help if needed. I have seen traditional monitoring systems and medical monitoring systems. I have not found one that will handle fire, entry, water and medical alert calls. Our heads are spinning from reading the ads on the internet. Does anyone have an opinion about where to turn? Can you refer us to a site where they impartially review these systems?
If my mother uses the panic button in the personal emergency response system, will the monitoring company help her by calling EMS and/or me? Would she have to be near a phone to answer the monitoring company?
There is a lot at stake and I want to be absolutely sure about the services I am going to get.