If you are moving, you know for a fact that the need to go over your things is a must. It is very advisable to conduct a general cleaning a week or two before the move. This general cleaning will enable you to sort your things properly. Considering how expensive the shipping and moving truck is, sorting your things properly is one of the things that you can do in order to save.
If you are on a time crunch where a one time big time clean up is too much for you, cleaning up one part of the house at a time is your best bet. This will give you a chance to look over a particular area of your house and its content in a short period of time. There is no no need to spend one day of cleaning alone if you can stagger and allot 1 hour a day in working at say, the kitchen and the living room.
Cleaning your house before moving will give you ample time to go over the things that you ought to bring and the things that you ought to give up. This is why it would be wise to do this a week or two before the actual day of the move so that you can dispose the things that you can do without accordingly. Those that you think would be of interest to others, you can sell. You can donate it to charity or whatever is it that you want to do without. The point is that you have seen and inspected these things accordingly.