Since a lot of my family is vegetarian, and includes people with shellfish allergies and gluten intolerance, this list may look a bit limited to those of you who don't suffer from such constraints.
1) Salad... always. The basic romaine, tomato, cucumber, basil, radish, and a dressing of olive oil and rice wine vinegar, is always a winner.
2) More salad. My family loves to put fruit in salad. One classic is the strawberry, avocado, papaya with lime juice, walnut oil, and a turn of black pepper.
3) Another is the crisp pear, toasted nuts, gorgonzola over mixed field greens with a little olive oil and white wine vinegar.
4) My FIL makes an amazing side dish of fresh corn (barely cooked in boiling water, or lightly grilled) taken off the cob, mixed with toasted walnuts, shredded basil, and a lot of grated Parmesan. The trick is to toss in the cheese while the corn and nuts are still hot, so cheese sticks to every bite. Then top with the basil just before serving.
5) Another FIL classic: hot rice, mixed with toasted pecans, shredded sage, grated Parmesan, and a hunk of butter. It's decadent and delicious, and dresses up left-over rice like nothing else.
6) Fresh bread. Duh!
7) White rice, of course.
8) When the weather is cold I love to make a huge tray of roasted vegetables. I use sweet potatoes, onions, brussel sprouts, cauliflower, carrots, cabbage... and I'm certain I'm forgetting a few.
9) My aunt makes an amazing quinoa salad that generally includes feta cheese, halved cherry tomatoes, diced cucumber, scallions, corn (fresh off the cob, if possible), and a can of chickpeas, all dressed with olive oil and rice wine vinegar.
10) Mashed potatoes (even if nothing is being served with gravy)