As far as losing weight, here's a couple of things that have worked for me:
1) Stop drinking pop (or lattes, etc.). I have dermatitis (extremely, extremely dry skin) and was told to cut caffine out of my diet. I did. Let me tell you, it felt _weird_ for the first while, maybe even a couple of years -- but mostly 'cause I kept slipping. Now, I almost can't stomach pop. About one can of Coke during the weekly game is all I can handle.
Replace it with water. Get a filter/treatment system/purifier if you need to. Water is _really_ good for you. It's more than just "emprty liquid".
2) Graze. When you're hungry, eat. When you aren't, don't. It's a "Well, duh!" statement, but most people don't follow it.
IMHO, that's because the idea of three squares is too ingrained which means that most people just eat more.
Don't worry about "spoiling your dinner". If you need a snack at 3:00, then have one. Understand that your dinner will be impacted and go with it. You'll eventually figure out what works for you.
Tonight I blew it and went to a barbeque, but yesterday would be pretty typical for me: A couple pieces of French Toast for breakfast, a sandwich at 11:00, an apple at 2:30, and a half a chicken breast (chicken Parmesian, yum) and corn at 6:30.
3) Listen to your body. I know that I'm _rarely_ just "hungry". I'm usually hungry _for_ something. Sometimes I have a real craving for protein, so I have an egg or a slice of lunch meat, or some beans. Sometimes, it's dairy, so I have some cheese (we always have at least one block of sharp cheddar in the house). Sometimes it's fruit. Anyway, it will take a while for you to learn what your body is saying, but it pays off. Big time.
4) Understand that junk food is junk. Use your discipline at purchase time. There is a whole aisle in the grocery store that is off limits, maybe two, depending on the store. No chips, no pop, no cookies. Don't even keep them in the house.
Yeah, it's a pain in the butt and uncomfortable, but this is probably the best thing you can do out of all the above advice. _Think_ about what you're sticking in your mouth and what it's doing to your body. Believe it or not, it becomes reflexive. Also, there comes a point where you actually _prefer_ an apple to Chips Ahoy.
I'm not going to lie and say that you can't tempt me. Milk and cookies (especially my wife's special homemade chocolate chip) or ice cream will sucker me in almost every time. And once I slip hard, I'll usually pack on a few pounds before I catch myself. Still, having developed the awareness gets me back on track reasonably quick.
A couple of "cheats" that I've found are a) if you're a "chips" person ;like my wife, try pretzels (the regular bite-size variety) with spicy brown mustard for a dip. A little high in sodium, but generally harmless. b) If you're a "sweets" person, fruit is your friend. Change up regularly (pears, apples, kiwi are all favorites) and a standby for a real sweet tooth is apple slices with caramel dip (the grocery store here actually has light caramel dip beside the apples).
Random information: orange juice and bananas are the two most commonly consumed fruit servings. They are also two of the sweetest (as in most sugar) fruit servings available. I'm not saying avoid them (I need my morning OJ like some people need coffee). Just don't rely on them.