Personally, James Whale's THE OLD DARK HOUSE is a favorite. It's beautifully shot, and the opening is incredibly tense. The plot has been used again and again, with films like Texas Chainsaw Massacre, etc... It is one of the few movies where I actually believed that when the group gets stranded, they have no choice but to stay in the closest house they come to.
From the director of The Invisible Man and more amazingness, watch the full film here: