Help in upgrading tires V6 Pony Package 2007 Mustang

I have looked everywhere and have asked so many questions yet NO one seems to be able to help me....so here it is. I desperately need new tires for my 07 stang....stock 235/55-17....I really would like to upgrade to a wider tire....do I do this front and back same size....will I have to make other adjustments besides have my tuner recalibrated to accomodate the new tire sizes? If anyone could help me with size suggestions and brands which are the best and also should I be going with an all season tire as this is my daily driver most of the year....more a motorcycle gal in the summer months! :shiny: If anyone could help I would greatly appreciate another Mustang owner's opinion and experience!!! Thanks for any help you may provide! Stinks being a girl....tired of getting ripped off because I don't know everything there is to upgrades on this vehicle...Oh yeah....I am a pretty aggressive driver if that helps on tires also!:gringreen