I have to agree with Nancy. 10 weeks to a half marathon, is not much time, especially since you say that you have not been consistently running. Fang, you were already training daily and building connective tissues, muscle and bone; you may not realize how much advantage you have over someone who is not currently on a daily or even consistent workout schedule.
With all that being said, when you do decide on a half marathon, here is a 3 day a week, 12 week beginner's program that I have used for several halfs. It's on my blog: http://www.sparkpeople.com/mypage_public_journal_individual.asp?blog_id=3413896. If you have any questions or can't understand it, please Spark Mail me and I'll help you with it.
As far as weight loss/nutrition goes, you can lose weight while training. I lost 13 lbs over a 5 month period while marathon training. I wasn't overweight to begin with - 130 lbs at 5'3" and I weighed 117 lbs the day before the race. However, just because I was marathon training, that didn't mean I could eat anything I wanted. I realized that I had to be extra careful with my food because I needed my biggest bang for the buck, nutritionally speaking. Every calorie I ate had to have the best nutritional benefit for me. I ate mostly whole foods and I cooked and prepared everything. Occasionally I would eat out and even then I would keep it to whole foods. My diet mainly consisted of:
PRE-RUN MORNING SNACK: Granola bar and water.
ON THE RUN (if more than an hour): Hammergel; if longer than 2 hours I would also take some electrolytes and liquid nutrition like Accelerade or Perpetuem.
BREAKFAST: eggs, quinoa, beans, fruit, spinach, whole grain cereal with 1% (not skim) milk, yogurt turkey bacon/sausage, soy sausage, feta cheese, whole grain toast, whole wheat wraps. Not all of this at one sitting, but I would mix things up. For example I would make spinach, beans, and quinoa the night before and scramble eggs in the morning. Mix all that together in a wrap with a little feta cheese and/or salsa, with some fresh fruit (not juice) on the side. Or mix yogurt, berries, and lowfat granola together.
SNACK: handful of nuts, a piece of fruit and some yogurt
LUNCH: Colorful salad with salad greens, red peppers, tomatoes, carrots, purple cabbage, broccoslaw, or any other veggie I had in the refrigrator. Top with chick peas, beans, and/or chicken or fish.
SNACK: Veggies, fruit, nuts, seeds, yogurt, plus 1-2 oz of dark (70%) organic chocolate
DINNER: Protein (chicken, fish, tofu, beans), whole grain (sweet brown rice, quinoa), and veggies.
SNACK: small bowl of cereal before going to bed or air popped popcorn (light or no butter - NOT microwaved)
I drank mainly water, but had 1-2 cups of coffee in the morning, and green tea if I wanted something else with my meals other than water.
My meals were not large and I don't eat until I'm stuffed - I only eat until I am not hungry. Eating several times a day also keeps me feeling full and I never had a sugar crash.
As far as what clothing to wear, you want to stay away from cotton. Cotton absorbs and holds onto moisture causing chafing, plus it just gets heavy. Look for tech fabrics. If you are on a budget I have found a brand called Aspire to be affordable and good quality for the price (you can find this in Sports Authority). Personally I like the running shorts with the built in panties because wearing undies on the run can chafe. I also like tri shorts, which are like compression (bike) shorts with a much small chamois in the crotch (also wear these commando). These are perfect for running in the rain or high humdity because regular running shorts will stick to your skin and ride up if it's wet.
As far as shoes go, you need a professional to analyze your gait to determine what type of shoes you should wear. Go to your local mom & pop running store - someone there will be able to help you. DO NOT go by brand name or by advertisements. What works well for one runner will injure another. And for gosh sakes, don't go into a chain sporting goods store and ask the clerk there. They have no idea and will probably hand you a Nike that looks cool or is in some hot color (not that there's anything wrong with Nikes - it's just what people buy because of advertising).
Good luck with your HM journey. If you plan it right you will have a good, challenging training period followed by an injury-free and successful race.
"God gave you your body as a gift, so you should take care of it." - My Mom