zucchini is a good one to start with, I think that was DD's first 'real' food. Followed by sweet potato and pumpkin sticks. Broccoli and cauliflower are great as they have their own little handle and don't need much cooking. DD loves yellow squash too.

Any vegetable really (as long as it is cooked so it's soft) is fine. I try and save some of our vegies from dinner to give DD the next night for her dinner, that way I don't have to cook something again for her. Cruskits are good (with vegemite or cream cheese/cheese spread or avocado), they melt in their mouths pretty much.

Pieces of meat are also good for them, even if they don't consume any of it they will get nutrition from it (specifically iron) just from sucking on it.