I'm not sure you are telling us WHERE you are finding the moisture/condensation. If it is on the floor, then It sound from the previous posts that everything sounds ok except that you don't have any insulation in your floor. If it is warm inside and the floor is cold, you will get condensation on the floor. If you have a lot of ventilation in your crawl space then air movement (wind) could substantially cut down on the effectiveness of your insulation. I would consider insulating and then covering it with a wind barrier like tyvek. This could be stapled directly to the joists (if the insulation isn't going to fall down and pull the whole mess down) or you could put 1/4" plywood up over (under) the insulation first.
I have lived in older houses with dirt crawl and no insulation and it is no fun, but it was from the floor being cold not moist. If you are running your heat and you have significant condensation, you might have some other kind of moisture problem because heated air in a home is relatively dry. Warm air is capable of holding a lot of moisture, but inside a heated house the air is usually very dry because it started out being cold and dry. There has to be a source of moisture to add to it to give it enough humidity to create serious condensation. If you still have c0ndensation after insulating then you need to keep searching for the moisture source. Insulation is still money well spent because you will be more comfortable and you won't be losing heat to your crawl (yes, heat goes up but a certain amount of it will also be lost down, even without air leaks). Other sources can be; water in the crawl; vent free gas heater; lack of exhaust fans in steamy bathrooms and kitchens; tight house.