We have recently moved into a new house and it has a Worcester Bosch 15/19 Heatslave Oil Combi-Boiler. Previously, I've always been used to a gas boiler with hot-water tank; and I've therefore got a few questions about how it works...

1 - is there a hot water tank, or is hot water supplied on demand? We have had a couple of occasions where there's been no hot water
2 - I have found the thermostat, and it's quite old, and in the hallway, which I always think it a strange place to have it, as it's the room you're never in. Is it worth upgrading to a digital one, to give a more accurate temperature, and what about moving it to another room?
3 - the CHS is obviously not on at the moment, although with all this rain, we've got close! Do I just put the controller on as I would a Gas Central heating unit, for the times we are in the house etc.
4 - finally, I have in the past looked at being able to turn on/off the heating remotely (i.e. from work) as my wife and I work odd hours that change very frequently. Is there a controller for the boiler that allows remote turning on/off?

Many thanks