What all is included in Red Dead Redemption GOTY edition?

Solution 1:

According to an official post from Rockstar:

Red Dead Redemption: Game of the Year Edition features the full, original Red Dead Redemption game - winner of over 160 Game of the Year honors - with a brand-new Hardcore single-player difficulty option, plus the wildly popular Undead Nightmare single and multiplayer offerings, as well as all the additional downloadable content, including all the DLC originally released as pre-order content as well as the Solomon’s Folly single player gang hideout and challenges (available for the first time on Xbox 360)

The additional DLC to which they are referring include:

• Liars and Cheats
• Outlaws to the End
• Legends and Killers
• Free Roam Pack
• The Hunting and Trading Pack
• Myths and Mavericks
• Solomon's Folly (previously unavailable on Xbox 360)

The game comes in a two-disc set, with disc one containing the main storyline and Undead Nightmare, as well as the DLC; the second disc contains the game's multiplayer.

For a more comprehensive list of the GOTY offerings, another Rockstar post goes into further detail:

• All Pre-Order Content
  • Deadly Assassin Outfit
  • War Horse Pack
  • Golden Guns Pack

Given the comments on that post, I believe it is safe to say the DLC is included on the disc, rather than individual download codes.