Before takeoff, the pilot got a weather briefing and called the airport manager at the destination. Reportedly, the destination airport was open and usable at that time. In flight, the pilot asked ATC about reports of icing in the Mt Pocono area and got a negative reply. While descending to the destination, rime ice accumulated on the plane. Due to the extra weight, the pilot held 100 kts on final approach and touched down 100 to 200 ft past the threshold. The 2600 ft runway appeared to be covered with only light snow, but as the brakes were applied, the pilot realized there was powder snow over glare ice. He considered, but rejected, a possible go-around since there was ice on the plane and trees at the end of the runway. Also, it was a dark night and the pilot was unfamiliar with rising terrain near the airport. He was unable to stop on the runway. The plane continued off the end and the nosewheel hit a ditch and failed. Runway 05 on the airport was 4000 ft long, but would have required a circling approach.