There are many brilliant foreign films, that, unfortunately, are often overlooked or dismissed by people who don't like films that feature subtitles. Many popular Hollywood films are actually remakes of foreign films - and most of the time, the original is far better. Some of my favourite foreign films include:
The Orphanage (Spain, 2007) - Without doubt, one of the best and most chilling horror films I've seen, due to the incredible atmosphere and suspense.
City of God (Brazil, 2003) - I don't usually like gang movies all that much, but this one is really touching and gritty at the same time. The cinematography is great, too.
Bad Education (Spain, 2004) - Like most of Almodóvar's films, this is really quirky and subversive. It's not particularly comfortable viewing, but it's definitely worth a watch.
Let the Right One In (Sweden, 2008) - The American remake was released in 2010, under the name Let Me In.
The Girl with the Dragon Tattoo (Sweden, 2009) - The 2011 American remake isn't bad, but I like how much more realistic the Swedish version seems. The characters aren't perfect-looking (one thing Hollywood did change), but why should they be?
Amores Perros (Mexico, 2000) - Three very different lives are affected by a horrific car accident. This film's often referred to as the Mexican Pulp Fiction.