South Park and the Simpsons (original). I also have to agree with Iceglow about QI, which is hilarious.

Originally Posted by
Cuchulainn
Father Ted
Green Wing
Seinfeld
Frasier
Reeves & Mortimer
The League Of Gentlemen
Morecambe & Wise
Alan Partridge
Nathan Barley
Blackadder
Only Fools And Horses
Friends
If there is any of the above you haven't heard of you should be smurfing ashamed of yourselves
Outside of the American shows, I only recognize Blackadder. Which is great.