Ray C. pretty well summed it up. I use moist spagnum peat moss in ziplock bags (poke some pin holes for ventilation) in a refrigerator set at just above freezing to store the acorns over winter. If you only put a few acorns (10-20) in each bag and you keep them cool enough it slows down the rooting and they aren't too tangled when you try to seperate them for planting.

Don't use a frost free refrigerator. They actually warm up well above freezing during the defrost cycle. A local nursery operator discovered that when he installed a min-max thermometer in a fridge and it was going up to almost 50 F.

Dan O.