Oh Happy Day made famous by Sister Act
• 2 music tracks in MP3 instrumental version
• 1 music track with vocals (cover)

Oh Marie made famous by Rod Stewart & Jools Holland
• 2 music tracks in MP3 instrumental version
• 1 music track with vocals (cover)

Oh Marie made famous by Jools Holland & Rod Stewart
• 2 music tracks in MP3 instrumental version
• 1 music track with vocals (cover)

Oh What a Beautiful Morning made famous by Oklahoma! (musical)
• 1 music track in instrumental version
• 1 music track with vocals (cover)

One Horse Town made famous by Blackberry Smoke
• 2 music tracks in MP3 instrumental version
• 1 music track with vocals (cover)

Outside made famous by Staind
• 2 music tracks in MP3 instrumental version
• 1 music track with vocals (cover)

O.D.'d in Denver made famous by Hank Williams, Jr.
• 1 music track in instrumental version
• 1 music track with vocals (cover)

One made famous by U2
• 1 music track in instrumental version
• 1 music track with vocals (cover)

Once Upon a December made famous by Anastasia (1997 film) (Liz Callaway)
• 2 music tracks in MP3 instrumental version
• 1 music track with vocals (cover)

Overdrive made famous by Ofenbach (DJs) & Norma Jean Martine
• 2 music tracks in MP3 instrumental version
• 1 music track with vocals (cover)