1) You should start walking. If you're comfortable running, go for it! Maybe walk about 5 minutes, run 2 minutes, walk 5, run 2, etc.
2) A good goal is to do about 30 minutes, mostly depending on your workout.
3) As many days as you can would be great. You can start off with three, like Mon. Wed. and Fri. and use days in between to rest up. Then add another day in a few weeks, then add another, and so on.
4) Given foods to avoid are junk foods and fast foods like cookies, chips, McDonalds. But things you may want to watch out for also are foods that have high fructose corn syrup, which is a weight loss preventer and overall bad for you. Be careful when eat carbs, there are good carbs and bad carbs. Stay away from white bread, and white rice. Whole grain is good.
5) Treadmills are great because you can adjust your incline. Try walking a fast pace, 3-4 mph while changing your incline every few minutes. It's a really great workout!
WATER. Drink water constantly throughout the day. It's so incredibly important. Think of doing the dishes. You have a full sink of dirty, greasy dishes, but you only have a cup of water. Is that really gonna get the job done? No. You need to replenish your body by drinking water.
WORKOUTS. Try wearing lots of layers when you run. As many as you can without getting overheated. It will help to burn more fat calories.
DIET. People try to starve themselves all the time when dieting and not even know it. You should be eating about every three hours to keep the metabolism going. (of course you need exercise to train your metabolism also) But make sure to eat fruits, veggies, and lots of protein. Your meals should consist of a 3:1 ratio of protein to carbs if you're looking for weight loss.
*Don't forget to have some sort of protein enriched meal within a thirty minute time block after your workouts. It's important to rebuild the muscles you broke down.
*Stick to a plan. Write out a schedule and stay with it. Have goals, which you already have to get to down to 220.
*Don't cheat yourself. You can exercise all you want. But if you have a bad diet, nothing will happen. And vice versa. Have an even mix of exercise and HEALTHY diet.
Good Luck, I wish you the best! :)
I'm a runner! This kinda stuff is my life.