Here's a simple family portrait I took at our living room that took no more than 5 seconds to do. All I did was to take a shot in front of a wall. The clean background can simulate a seamless background at a studio.
The trick to making it work is the lighting. If you use a pop-up flash or direct flash, the subjects' shadows will be clearly visible on the wall, which won't look very good. Instead, you have to use a soft light source such as light from a large window (as long as the sun is not shining through it directly on your subjects) or bounce flash (with the flash facing away from the subjects). In the shot above, I used both ambient light (from a patio door behind the camera) and flash bounced to a ceiling camera rear and right, on TTL mode.
If you don't have an external flash, try using ambient only. If the ambient is too dim and a popup flash is all you have, at least move the subjects away from the wall so that their shadows hopefully don't show against the wall.