Continuity mistake: Mary (the checkout clerk who later appears in Shaun's garden as a zombie) works for a fictional supermarket chain, "Landis." But in the opening montage, all the till screens display "Welcome to ASDA" (Asda is a real chain of supermarkets in the UK). (00:03:35)
Continuity mistake: At the beginning of the film, when the camera pans across the road towards Shaun's house, the silver Renault badge on the hood of Pete's car is missing, but when Shaun goes to work that morning (Pete sits in the car), it's there. The badge disappears again later in the film. (00:06:55 - 00:24:25)
Continuity mistake: As Shaun is giving the opening pep talk to his co-workers at the appliance store, his tie flips backward and forward several times. (00:09:00)
Continuity mistake: The red ink on Shaun's pocket at work changes from a solid blob to one with a few spots above it back to solid. (00:09:50)
Continuity mistake: In the beginning when Shaun is at work and is talking with Liz on the phone, when they are done he puts the phone down. Two cuts later we see him putting it down again. (00:11:20)
Continuity mistake: In the scene where Shaun meets Yvonne for the first time in the film, the nametag on his shirt is visible and then gets covered by his jacket as the shot changes between the characters. (00:12:40)
Continuity mistake: Shaun's "To Do" list, which he writes on the whiteboard, changes. He doesn't write an exclamation mark, and he swipes the marker pen through the word "OUT." However when we see it the following morning when he awakes, there is a exclamation mark after the word "OUT", and the lines he drew through the word "OUT" have moved and are now underneath the word. (00:24:05)
Continuity mistake: When Shaun goes to the newsagents after the dead rise, he gets a drink out of the fridge, which has blood-stained hand prints on. He slips on what we assume is blood as he walks away, yet on the way in and as he leaves the shop you can see behind him that there is no blood or any other liquid on the floor. (00:25:35)
Continuity mistake: In the scene where Ed smashes the ashtray on the zombie's head, his right hand goes to pick up the ashtray. In the next shot, his right hand is empty and in the close shot of the zombie we see the ashtray in Ed's hand again. (00:30:50)
Continuity mistake: After Ed kills his first zombie, there is a blood stain on the right of his "I Got Wood" emblem on the t-shirt. But when they are throwing objects at the two zombies in the garden, this blood stain has somehow vanished. (00:30:55)
Continuity mistake: When Shaun and Ed bring out the basket of mugs, pots and toasters etc., to throw at the two zombies, in one closeup we see Ed pick up a mug and a saltshaker, but in the next shot we see him throwing a wooden mugtree. (00:32:00)
Continuity mistake: When throwing records at the zombies, watch when Ed throws one at the girl. As he throws it, her head is to the left but when the camera shows a close up when the record hits her, her head is to the RIGHT. (00:32:45)
Continuity mistake: When Shaun and Ed repeatedly hit the two zombies in the back garden, no blood appears on the cricket bat or shovel, however it does splatter onto their shirts. (00:33:20)
Continuity mistake: When Shaun and Ed are looking upstairs for Pete and Ed is about to go up, Shaun stops him with his arm. At first his arm is under Ed's hand. When it cuts, his arm is over Ed's hand. (00:34:00)
Continuity mistake: After Ed and Shaun make the plan to save everyone, we see the close-up shot of the TV where the announcer is saying that nobody should try and save their friends and family. If you look at Shaun, you see the handle end of the cricket bat in his right hand, and he is facing the TV screen. In the shots immediately before and after that, Shaun is not only turned away from the TV, but the handle is in his left hand. (00:37:00)
Continuity mistake: After Ed and Shaun pull up to Phil and Barbara's house, the garbage bins move around by the time the zombie falls backwards onto them. (00:40:30)
Continuity mistake: When Ed and Shaun use Pete's car, the rearview mirror changes its characteristics between shots. Things such as being large with perfect 90° angles to being smaller and having curvier edges or being attached to the black unit on the car ceiling to being attached to the windshield. (00:40:50 - 00:41:40)
Continuity mistake: The field in front of Liz's flat is large and unfenced. Yet, when Shaun climbs up to her window, there is a fence not more than ten feet away. He couldn't have run round the side as the sound of the zombies are coming from the same direction. (00:46:25)
Continuity mistake: When Ed drives Phil's Jaguar, its rearview mirror disappears and reappears repeatedly. (00:47:15 - 00:53:35)
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