it depends on what you are doing... for example, if you are running mostly, you should get running shoes.
if you are going mostly aerobics etc., you will want a cross trainer.
i run mostly so i use running shoes. i have wide-ish feet so i have the brooks adrenaline (wide toe box!) and i love them. however, i know that i am a pronator so i need the extra support. you should consider going to a running store and getting fitted for shoes. if it's something you plan on getting into for the long term.