When should start lifting weigts you were 260 pound 2 weeks ago and now you are 251should you stay with cardio or start lifting weigts?

This would depend on your aim. If your are looking to loose weight I would suggest supplementing your cardio workouts with weight training, performing the weight training before the cardio as this will use up glycogen so you burn more fat during the cardio. Also it will increase your muscle mass, which will increase your metabolism, the rate that you burn energy. Also try going for a walk/run first thing in the morning, before breakfast as your glycogen stores should be empty so you will burn more fat than if you do cardio any other time of the day.