Here are a few helpful tips for Sonic Unleashed (Xbox 360 version).
Xbox 360 Achievement Tip: “Getting the Hang of Things” You can get this achievement easily by obtaining an S-Rank on Windmill Isle Act 2. Just play through the level while continuously boosting, collect around 400 rings, do all button prompts correctly, and don’t get hit by an enemy. Easy achievement.
Unlockable Tip: Eggmanland Hub World. You must defeat Perfect Dark Gaia and beat the game to be allowed to go here.