Bubble refers to water extraction with ice through mesh bags. BHO is solvent extraction with Butane, or other solvents. Iso extraction can make BHO-like extracts, basically just by briefly rinsing the buds.
Everyone has their preferences on drying, always hanging the branches upside down, sometimes trimming the big leaves first and small ones several days later, or full trim first, or full trim last.. They say you should seal it airtight for curing when the stems can break easily, but I've noticed that the stems dry out first from the top (when upside down... actual 'tops' are at the bottom), so you can cut the branches into 1' lengths and dry them like that. Basically when its lost half its weight, start the curing phase, be careful of mold. The buds shouldn't feel damp to the touch, or just barely damp.. If you pinch a little, and you feel a slight dampness, thats the perfect time to lock it away for 2-3 weeks for curing.