I don't know a lot about the currency, except that 1 Euro is about 67p but someone on here will probably know a bit more. You'll have to prepare for some things before moving over. For a start, a lot of people in rural French villages won't speak much English so you'd need to know a bit of French.
I can help with the electrical side of things though. Firstly, you'll need to change the plugs on all of your UK electrical equipment if you take it over there. French power outlets are round with 2 pins and a stub for earthing (you may know this already if you've been on holiday there), but they use the same voltage so you should be ok with just changing the plugs. The one thing that might not work over there is your TV and video. French TV signals are in SECAM and we use PAL-I, so you might get a picture but it will probably be black & white with no sound. Stereo and other equipment though should be fine. If you want to get TV from the UK, you can with a satellite dish as the Sky Digital signal covers most of Europe and the signal in France is pretty strong. click here for more information. You can also recieve the regular BBC and ITV channels free anyway if you don't want to pay for a subscription.