Vx genuine batteries are great value and what I would fit. Halfords stock calcium batteries but are very expensive but they are meant to be very good.
When changing the battery, turn on your ignition for the instrument lights, turn off, remove the keys from the ignition and remove from inside the car. You now have a short while to get to the battery and disconnect it without the power sounder alarm going off.
Might be worth loosening the negative terminal first to give you a bit of a headstart.
No need to reset anything other than your clock and radio once new battery is reconnected. See if you can get your altenator checked to be sure that its charging the battery.
And one more thing, if you're not buying a Vx genuine battery, make sure that the terminals are of the same configuration as the battery that you are removing.