Baby Driver was a full-on showcase for Edgar Wright's love of music, and more importantly his love of pairing action to interesting musical choices, but both were present in the Cornetto Trilogy too.
Shaun of the Dead's soundtrack includes a number of classic British rock bands, most notably Queen and The Smiths, but also includes a score filled with musical motifs that reference the work of George A. Romero (and indeed has cues taken from Dawn of the Dead itself). It also adds some hip-hop and electro to comic effect, like with Man Parrish's Hip Hop Be Bop (Don't Stop), the great car sequence to Eighties Matchbox B-Line Disaster's Mister Metal, and, of course, the stunning Don't Stop Me Now scene where they beat John the Bartender with pool cues.
Hot Fuzz likewise uses its music as a means of referencing its chosen genre, although the score does feel a little more generic here. Its soundtrack choices, however, are again excellent. Supergrass' Caught by the Fuzz is another classic example of Wright's ability to fuse music and action, but overall it doesn't stand out quite as much as Shaun's does.
Winner: Shaun of the Dead.