Delete the Documents\My Games\Rigs of Rods\config folder.
Start RoR (it will be in 800x600 windowed mode), go to Settings -> Render System and set the Video Mode to your monitor's native resolution. Restart RoR.
Go back to Settings -> Render System and enable full screen if you want it. Restart RoR again.
If that fails, please post a screenshot of the error and upload your RoR.log.