You have to experiment and see what works for you. Typically though, starchy veggies should probably be avoided by anyone trying to lose some weight. But, I've read on here about people having immense success keeping said starches in their food plan and losing weight dramatically.
I personally feel you will lose weight no matter what once you cut out all grains. Just don't make squash and sweet potatoes the only veggies you eat Your body needs variety too!