We Eat It Because It's There
Let's be real for a minute. There is a reason we eat all of these unhealthy foods: it's because they are there. It's easy to sit in front of the TV with a bag of chips after a long day of work and an epic battle to get the kids to bed. Those chips are probably not your favorite and you probably aren't even hungry – you eat them because they are there.
The simplest path to eating healthier is to purge some of the junk. You don't have to do all of it at once; I suggest eliminating one or two unhealthy foods every week and replacing them with better options. If the food isn't in your house you won't be tempted to eat it.
A great rule of thumb is, if you can’t pronounce the ingredients you probably shouldn’t be eating it. Check out this facebook video we did with Life of Dad about reading nutrition labels.
I understand it's going to be nearly impossible to completely get rid of the dino-shaped chicken nuggets and mac n' cheese. That's fine, just make small improvements. They are likely to snowball and help you create healthier eating habits.