I don’t think this is what the hobby means by Old School Renaissance. That said; if you fancy a bit of retro clone action with D&D then you can download Chronicles of Mystara.
The download is a revamp of two classic D&D comptuer game titles; Tower of Doom and Shadow over Mystara. It’s a feast of side scrolling beat ’em up action.
The revamp supports up to four players, two models, and easy drop in/drop out action. You can grab it on Steam, PlayStation Network (if not today; tomorrow) and Xbox Live Arcade. It’ll land in the Nintendo eShop for the Wii U soon.