If you want an idea for diet, you could try what I do:
Breakfast: Wholewheat cereal (I use Shreddies cos I don't like anything else)
Lunch: Same as breakfast
Dinner: Piece of meat (chicken breast in the George, or salmon in the steamer) with as much veg or salad as you can handle. Bit of dressing is fine, just grab a low-fat one.
Do that during the week, usually quite easy because of work taking up the rest of the time. At the weekend, eat and drink what you like. That's when I'll grab a takeaway on Sat night, and a bottle of wine. Maybe a bag of crisps to eat during the F1.
No-one ever got fat eating veg or salad, so just eat as much as you can, fill yourself up. I'm sure that nutritionally my diet could be better, but it works for me as that's pretty god damn healthy during the week, but it means I can still satisfy my cravings at the weekend so I never feel like I'm missing out. Add in an hour of cardio 3-5 times a week and I promise you the weight will drop off.
Plus, ALL THE NOMS AT WEEKEND