I feel better about how I LOOK when I'm slimmer, but my weight doesn't affect how I feel about MYSELF.
I have two kids. I think I started out around 160 before kids. I'm 5'9", so that's not skinny, but it's not bad either. I gained at least 40 pounds with each kid. I lost the weight (all but about 4 pounds) after the first time. I'm two years out from my second pregnancy and still have about 12 pounds to lose to get back to where I was (164). I'm not sure if I will lose it, but, to be honest, I'm not really trying that hard. There are just so many more important things to worry about in this life. My kids and my husband think I'm pretty no matter what I weigh and those are the only people who's opinions matter to me.
I feel like I'm a little heavier than I want to be, but it's not that bad. I look fine in jeans. I've never had great legs, even when I was a teenager, so I don't expect to look that great in shorts. I've accepted that long ago, so that doesn't bother me. I just don't wear short shorts. I find that as long as I choose my clothes with a realistic eye and don't try to fit into something too small or inappropriate for my age, I think I look fine. Of course, I don't look so good in a bathing suit, but I don't try to. Most people at the pool don't look good in a bathing suit. So, I figure I fit right in. When I really want to look my best, I have a corset I can wear under my nicest clothes. That takes off about a dress size, but isn't comfortable enough for everyday wear.
Your view of yourself shouldn't depend on your weight. If you're an unhappy fat person, you'll likely just be an unhappy, hungry skinny person if you manage to lose it.
Now, I'm assuming you're a little overweight. If you're really obese, that's different. All that extra weight will make a big difference in your quality of life. It makes it harder to do things and puts you at a higher risk for all sorts of health problems. In that case, losing the weight may or may not make you happier, but it will make you healthier, and that's a worthy goal to pursue.
Also, if the reason you think you look bad in shorts has more to do with your cellulite than your actual weight, then that's really pretty hopeless. Losing weight does not affect cellulite. It reduces it a bit, but you cannot actually get rid of cellulite. I don't really want to get into what cellulite actually is, but it one of those things that once you have it, you'll always have it. In that case the best bet is to just wear longer shorts.
I've never tried weight watchers, or any formal diet program. I do use the treadmill at the gym for an hour twice a week, but that's about it. When I do get really serious about losing weight, here's what I do. I stop drinking soda and replace obviously unhealthy things in my diet (like cookies and bacon) with healthier alternatives.