What foods are easy to digest?

I would recommend foods that are low in fiber and low in fat.
This doesn't mean you should avoid fiber altogether. The nutrient works to prevent diseases such as colon cancer, diabetes, and heart disease.
It´s best to consume soluble -- as opposed to insoluble -- fiber. It takes a longer time to leave the digestive system. Good sources of the soluble fiber include oat bran, barley, the flesh of fruit (as opposed to the skin), and navy, pinto and lima beans.
Foods that are easy to digest include white bread, white rice, cooked vegetables, soups, plain cereals and rice porridge. Chicken soup is highly recommended. It has natural anti-inflammatory properties, and can also help to balance your gut chemistry, keep you hydrated, and get protein and good minerals into your system.
Fish is easy to digest for two reasons:
*Fish has a high proportion of muscle tissue protein and a low proportion of fat and connective tissue protein holding the muscle blocks together.
*Fish muscle protein is made up from short-length fibres.

Stay away from spicy, greasy and sugary foods. Foods that commonly cause stomach sensitivities are coffee, alcohol, processed food, spicy food, tomatoes, wheat, dairy, soy, citrus, peanuts and corn. As a rule, meals should be as simple as possible. For people with a sensitive stomach, it is important to eat small portions of food at regular intervals, rather than indulge in large meals consisting of many food groups at one time.
Avoid chocolate, alcohol, caffeine, carbonated drinks, the artificial sweetener sorbitol (found in sugarless gum and mints), and fructose (the simple sugar found in honey and many fruits).
Some fruits that are easy to digest include apricots, banana, cantaloupe, canned fruit cocktail, grapes, honeydew melon, peaches and watermelon.
If you want to eat vegetables, go for alfalfa sprouts, beets, green/yellow beans, carrots, cauliflower, celery, cucumber, eggplant, lettuce, mushrooms, green/red peppers, potatoes (peeled), squash and zucchini.
Ask your doctor to test you for lactose intolerance (the inability to properly digest milk products), or celiac sprue disease (a serious disease in which foods with gluten can damage the intestine). These digestive ailments can cause diarrhea, bloating, and cramping.
It might also help if you keep a record of the foods you eat, and their effect on you. Since different foods can impact people in different ways, keeping a symptom journal can help you and your physician figure out what works for you.