The House is the target area made up of rings. In order to score in each end, you have to have stones in the house that are closer than any opponent stone to the center.
The Hammer is just the name for the last throw of an end. In each end, the team that has the hammer has the advantage, because the last throw can clear opponent stones and such. You have a better chance of scoring if you have the hammer. If you score in an end, you don't have the hammer in the next end, so you always try to get as many points as possible when you have the hammer. In some cases, if you are only going to get one point, you might clear the house and take no points so you'll have the hammer in the next end.
Each team throws eight stones per end, two per player. This means that the maximum score in an end is eight points.