looks like the bhuts I got from Cappy last year...they were pretty gnarly and very extreme...I would bet my bottom dollar it is either a Bhut Jolokia, Dorset Naga, Bih Jolokia, or Naga Morich, but my money is on the Bhut...
as far as the bottom leaves go...it's normal for the bottom leaves to yellow and eventually fall off...I have always pinched the bottom leaves off when they start to yellow....they will eventually die and fall off anyway so I hasten the process to keep the plant from putting energy into leaf repair...