Just the other day I was looking at a video a client had made for him. It's a great video--he sounded natural and compelling, the videography was great, the sound was fabulous--all in all, a great product. This was, by the way, produced by professionals. Yes, it was done on a shoestring budget, so there were no bells and whistles, but here's the thing that's important for you to know. To get a good background, the speaker was placed in front of a doorway. It was a great concept--light background behind him but surrounded by rich wood paneling. There was only one problem. There was a chandelier in the room behind the speaker. It was the same color as the walls of that room so it's barely visible. Unfortunately, when it IS visible, it looks like the speaker has a devil's horn sticking up out of his head.
What does this have to do with photography? I suspect you've already guessed. When you're setting up a shot, look carefully through the viewfinder to see what the area of the shot will be. Now, look away from the camera and carefully scan the area for annoying stuff that will detract from the photo. You don't want to discover it after you get home and decide it's such a great shot you really want that one to be enlarged to hang on your living room wall only to realize there's a tree branch "growing" out of your son's ear or a faded profanity on the wall directly behind you. I once say the most fabulous shot of a child in front of a Japanese temple and there, just off the path, was a Coke can.
It's the little stuff that can make all the difference in how your photos turn out.
If you're just taking a few candid shots for your scrapbook it may not be that critical, especially if you have quickly-changing scenery (it's pretty tough to stop to look carefully at the background when your three-year-old is blowing out the candles on his birthday cake) but when it's an important shot, try to take that little extra time to get the best shot you can.