Problems with electics fuses on a 2000 1.4 Astra?

I have a 2000 Vauxhall Astra 1.4 16v and I am having some problems with electrics. When I am dirving a warning light appears under the rev counter. It looks like a radiator symbol. This was coming on a lot when I was travelling on the motorway last week. Last night I was driving home and the brake lights were permanently on. Was was more wierd was that when I pulled over I put the ignition on and pressed the breaks and all the warning lights on the dash were displayer along the the central locking opening and closing when I took my foot off the brakes. I think that it may have something to do with the fuses as when I am driving at night the lights for the hot and cold air do not come on and the air conditioning light display does not come on when anymore when I press the button. Does anyone have any ideas beofre I take it to the garage as I do not want them to rip me off.