I think the best answer to this is to pop along to your RFD and handle as many Shotguns that fall into your budget, I would recommend an O/U for the shooting you've described. You will know when you have picked up the right gun for you, it will just feel natural and comfortable. Giving you names of manufacturers and models is a pointless exercise. Its also worth having the gun fitted, it doesn't cost much but will usually make a huge difference to your shooting.