Raw food means food picked from the garden or purchased in the produce section of your grocery store. It is unprocessed and uncooked. If it's been heated past 118 degrees F. it isn't raw.
Raw food contains more nutrients than cooked food. When food is cooked, the vitamin content decreases due to vitamins that are heat sensitive. The main reason is that all the enzymes are preserved in raw food, so that the food can be digested and assimilated without the body having to borrow enzymes from other areas, i.e. metabolic enzymes (used for other important processes in the body-repair, growth, maintenance of health.
Other than the reasons given in the first 2 questions, when you eat foods raw (and preferably organic), you are a. being "green" environmentally, by not using cans, Styrofoam, packages, plastics or glass that are containers for most processed foods. And b. You are skipping the dyes, sugars, salt, trans fats, artificial colorings, high fructose corn syrup and other unnatural ingredients that most packaged foods are loaded with.
Most definitely. While many vegetarians can be overweight, there are very few people who eat a mostly raw diet who are overweight. Your body will naturally and fairly quickly find its best weight. I lost 35 pounds on raw food, eating as much as I wanted. I was never hungry and never felt deprived. See my first raw foods book, Lose Weight with Live Foods for all kinds of recipes and ideas for going raw.
A vegan (no animal products) raw food diet consists of fruits, veggies, nuts, seeds, fungi (mushrooms), and sea vegetables. Delicious nut butters can be purchased raw. Delicious ice creams can be made from fruits and nut milks.
No, although I went 100% raw, cold turkey (excuse the language), some people would prefer to start gradually. You can add more raw foods in several ways: a. by making 1 of your meals every day entirely raw; b. make several meals a week raw; c. eat something raw at every meal. How easy is that? Most people already eat salads and fruits. You can add raw nuts for snacks.
Buy a good raw foods recipe book and begin to explore some of the delicious ways to prepare raw foods. I recommend my books, Lose Weight with Live Foods, Go Green and Get Lean, and my newest one, Chia Seeds: Bursting With Energy, which contains over 150 mostly raw recipes using chia seeds-similar to flax seeds. Chia seeds contain beneficial Omega-3 fatty acids, along with many vitamins and minerals. This book explains the multitude of benefits along with recipes for using chia seeds.
Here's a Kirlian (high energy discharge) photograph of some Chia seeds and a human finger tip (photo by Bruce Rawles):

A good knife, vegetable peeler and cutting board are the basics. A good blender with a strong motor can help you make smoothies, raw soups, ice creams, sauces, spreads and more. Additional equipment would be a food processor and dehydrator.
For every favorite fast food or junk food you eliminate, it won't be difficult to discover a similar substitute. Fruit smoothies can replace milk shakes. Dehydrated cookies from nuts and sprouted grains can replace store-bought cookies. Raw soups are delicious and there's even raw spaghetti and pizza.
Everyone is different and has different reasons for wanting to eat raw; however, if you eat more raw foods, you will lose weight, have more energy, require less sleep and improve your health and mood in many ways. The more raw you eat the sooner you'll experience the benefits.
Think about it. Though organic food can cost more, consider shopping at farmer's markets; buy food in season; grow a garden. Whole foods do not have a huge marketing plan invested by the food industry. How often do you see a television ad for an apple, a fresh pineapple or a bunch of carrots? There's little money spent in fancy labels and packaging. Check out a bag of potato chips --- usually around 3 ounces with half the bag of chips and the rest air. Calculate what it costs for a pound of potato chips and compare that to a pound of potatoes. There's no comparison. Over-all, by reducing your intake of packaged foods and eating foods whole and unprocessed, the over-all cost is less. A carton of orange juice (which will be pasteurized or flash-pasteurized) will cost a lot more than you squeezing a couple of oranges for a glass of orange juice.
Cut up apples, add raisins to their lunches, raw nut butter on celery. Buy mini-carrots. Easiest of all, make smoothies for the entire family. Use their favorite fruit juice, a banana, some berries or other fruit, and a handful of leafy greens (kale, spinach, Romaine) per blender. Blend and drink. They'll never taste the greens with all the fruit and they will be getting so many vitamins and minerals, also fiber. Skip the soda pop and those high fructose corn syrup-laden drink cartons containing little juice and lots of additives.
By all means, NO. If you are diabetic, you should monitor your blood sugar; by eating 100% raw, you will improve. Let your physician know of your diet if you have any medical conditions. It's very important. Lots of greens can thin the bloods (vitamin K) so if you're on a blood thinner, consult your doctor.