What are the best vegetables to eat?

I am trying to cut calories but still get the nutrients I need, while eating in a university cafeteria. There is, I think, a salad bar — I have not been to that cafeteria branch yet — but at the branch downcampus there was one with a pretty good selection.

There was:
bagged lettuce with cabbage and carrots
spinach leaves
dark mixed greens (spinach, anise, cabbage, etc)
cubed lean turkey
cubed lean ham
shredded cheddar cheese
chopped hard boiled eggs
whole hard boiled eggs
croutons
a couple kinds of salad dressing (but I never eat it anyway)

and then it varied, but there was at least some of the below:
cherry tomatoes
kidney beans
chickpeas
sliced mushrooms
peas (not in pod)
green beans
baby carrots
asparagus

Anyway, what is the best stuff to put in my salad, and how much of it? It will be pretty much my whole meal, and I only get to eat once a day. I was thinking probably 1.5 cups of dark greens, plus a little turkey (less salt), an egg, four cherry tomatoes, half a cup of
kidney beans, five or six baby carrots, and some mushrooms if they’re there.

I know it is not a whole lot… especially for a 19 year old… but I am limited by my meal plan to one meal per day, and by my budget strictly to the meal plan. (That is, I can’t afford to eat more than one meal per day by buying supplemental food.)

But I want to know, is this healthy for a salad? What should the portions be? (I do not really know because before this I just ate whatever crap I wanted to, which took a big toll on my body.)
Oh, also I would have a glass of water (or should I have skim milk or soy milk?) and either an apple or an orange, and a banana.