Factual error: The records that Shaun and Ed throw at the zombies in their garden shatter when they hit the wall. Only old fashioned 'shellac' records shatter like this -yet all the records were titles released after the introduction of "indestructible" flexible plastic records.
Factual error: The game "Timesplitters 2", which is being shown throughout the film, does not say "Player 2 has entered/left the game" on any system that it is released on, as shown at the start and end of the film. (00:04:25)
Answer: "Burn Down the Sun" by Daniel Mudford & Pete Woodhead, according to this site: http://musicfromfilm.com/movies/shaunofthedead.php. According to http://www.discogs.com/Various-Shaun-Of-The-Dead-Music-From-The-Motion-Picture/release/402748, it's not on the soundtrack (as it's just background music).
David R Turner