How Fat is too Fat

Throughout my life, I've been what people here (in North India) politely refer to as healthy. What that basically means is someone who's definitely fat beyond fit, but not quite obese. Up until a month ago, I was okay being the bulky one among my set of friends and didn't even mind the occasional fib on my weight. Recently though, I discovered to my surprise that I now weigh close to 77kgs. Now that might not seem like a big problem, but when you're 5'8'' tall and the spare tyre begins to show, it becomes a problem.

I have since decided to take up some sort of excercise regimen to cut down on my flab. The way I saw it, I had two choices, give up beer, or start excercising. If you know me, you know that giving up beer is definitely not a possibility. So there. I now go out walking every evening (actually I only started two days ago) for about 40 minutes. I figure I cover about 2.5 kms in that time judging by the size of the park. I intend to turn my walking into jogging by the end of next week. Let's see how this goes. Any advice of course is appreciated. Keep in mind though that this is the first time in my life that I am doing excercise for the sake of keeping fit, and other than roller skating, I've never really taken an active interest in any sport.