Many people who love the hobby of photography shy away from taking photos of people. It is a challenge to get a good shot of some especially those who don't want to be photographed. When I was little, we visited my great grandmother's house Christmas Day. My grandmother's brother had one of those old movie cameras with the big, bright, brilliant light on it. Did I say it was bright? I remember seeing that light coming from the kitchen and heading toward the living room (where all the people were sitting around talking). As the light approached, many (mostly women) would scatter, running from the movie camera, unwilling to be immortalized on film.
If you are trying to get a good photo of a small child or baby give them something to hold on to or look at. Have them busy with something and then take photos of them. One of the best ways to "get them busy" is to have a young child read or look at a book. You can get some great facial expressions from them when they are involved with a book. Even younger children can hold a favorite toy or just a piece of fruit. If you hand a young child an apple and they happen to stick it in their mouth no big deal and it could make a cute photo. If you have more than one child give them something to do as a group. One could read to the others. Try to keep their faces close. If they are too spread apart the photo could lose interest. At Christmas it is nice to have decorations handy for props. Plug in a string of tree lights and place them in the lap of a child or children. Snap away! Another fun time to take photos with children is while decorating or eating Christmas cookies.
When taking photos of adults the same kinds of strategies can apply. If you give them something to do, they will appear more natural and not "posed" or stiff. If there is nothing handy to physically give them something to do get them engaged in a conversation about something they find interesting. This will also help loosen them up for more natural photos.
Use your portrait setting on the camera. This will make your subject in sharp focus while the background will be blurred. But, just because it is blurred, don't forget to look at the background. You may have the best family portrait of the whole year but if the background is distracting you won't be pleased for long. There is only so much you can do in Photoshop. If everyone is visiting and they are wearing clothing that doesn't look great jumbled all together in one big family photo switch to black and white (you can use just about any photo-editing software to convert color images to black and white later). In black and white, no one knows Aunt Mary is wearing bright pink and Aunt Jane has on an orange sweater with brown stripes even if they are sitting right next to each other. Think about lighting side light from a window is wonderful for indoor people shots. Lighting still an issue, then turn on all the lights you can find. If you still need to use flash maybe just fill flash make sure there are no mirrors or reflective surfaces in the photo to shine the glare back at the camera. Take photos at eye level but that does not mean every single one have some of people sitting, leaning forward just a little, and looking up slightly this is a good pose for just a plain ol' sitting & smiling photo. If you are taking photos of kids fill the frame with their faces. Remember that placing the subject off center in th e photo creates more interest. If you have them looking in a certain direction be sure to give them "space" in the frame to look into. When filling the frame with a face -- beware of the giant nose that a wide angle lens can create and know your minimum focus distance. If you are gettimg too much of the "big nose" back up a little and use the zoom.
The best way to ensure you will have some good photos take a lot of them! Digital makes it easy. I remember when I was using film. It would take a couple rolls of film to get just a couple good shots of the kids together and alone. Now I can take however many I can fit onto the memory cards (and I have extra memory cards and batteries!). Also don't rush yourself take your time to see the composition of the photo that you want. Don't forget to add variety to your photos that is why I say take photos at eye level (but not all the time). Having shots from different angles adds interest.
I have cute photos of my kids. I also have some not so cute but we won't go there. There are quite a few good ones of my son (about 2 or 3) sitting on the kitchen counter while he was "helping" me mix up batter for a cake or brownies. There is one photo of my daughter that I just love. I had received a delivery of a large piece of fabric one day. She helped me open the package. At the time I believe she was also about 2 or 3. We took out the large piece and threw it into the air in the living room like a parachute. It came down on us we did this a few times and she was laughin g a lot. My camera was close so I grabbed it and went under the fabric. When the fabric went up again I had the camera right there for a great face shot.