Hair Style Help

I need help with my hair desperately. I need some style. It has been way to long since I got my hair cut and I am hoping to get it cut and colored this weekend but I can't decide what will look good on me. I love these rich deep brown colors but my roots come in lighter and my grey shows to quickly if I try to go darker. Also, as I get older I think I look younger with shorter hair instead of longer but I'm not sure. It is so hard to pick out a style for my hair, which is thick and wavy, and my face which is round and full. Ugh... I need help. I want to feel stylish and cute so I need to pick one of these styles but which one?