A questions on worlds and rulesets

[nytehunter]

I was wondering do different realms need their own rulesets? like would the Dragon lance realms have a different rule set then the Forgotten realms?

[Valarian]

No, you'd use the 3.5e (or d20_JPG) or 4e rulesets, depending on which D&D game system you're using. You might like to customise it slightly by adding a different desktop file in to the frames folder of the ruleset. That would give it a different backdrop for your campaign.