Personally, I like the "moment captured" type of photo but often folk want a traditional "smile for the camera" picture. This is often the case when shooting events: weddings, baptisms, retirements, and the like.
When it comes to these pictures, you should have an edge over the hired professional shooter. You know the subjects. You are a friend. Getting a good, warm smile should be easy. Thanks to the instant feedback offered by digital cameras, you will know when you have the picture locked up. Don't stop shooting until you're happy with the picture. But, possibly break your shoot into two or more takes.
If getting the right image is difficult, don't subject your friends to the "just one more" torture. Take a break. Give your subjects a rest. Don't tell them that you are not happy with the pictures. Just move on. Later, try again without making too big a deal out of it. Keep the shoot relaxed and the good images should just flow.
|Bright, contrasty sunlight mixed with shade is tough to shoot.|
Lastly, watch for props. The couple above are celebrating their retirement, of that there is no question. Incorporate the prop into the picture neatly, with as little wasted space as possible. Keep your picture tight and get immediately to story at hand.
Keeping your shots tight and not requiring a lot of cropping after the fact will keep images, even from small point-and-shoots, large and detailed enough for at least an eight by ten inch print.