the reasons for pre-washing are mainly...
1. to wash the sizing out of the fabric (so fusables will adhere, and just to get rid of it)
2. pre-shrink...to make sure the fabric will not shrink after made into your project
and
3. to ensure colors are stable. so nothing bleeds in your finished project.
some people pre-wash everything. some people prewash nothing. some people pick and choose what needs to be prewashed.
if you are washing precuts using one of the zippered net laundry bags made for delicates can cut down on the mess, helps keep everything from tangling together and excessive fraying. and you can throw them right in the dryer. and if you are washing because of the shrinkage issue and the item will be washed as a finished item (like a bed quilt) you should throw the fabric in the dryer now too. it is going to do its 'best-shrinking' in the dryer.
all cotton fabrics will have to be ironed/pressed after prewashing, no way around it, you wash out the sizing which keeps it 'crisp/pressed' off the bolt. so if you have a lot of new fabrics to wash make an afternoon of it, set your ironing board up at a height you can sit on the couch in front of, put in a favorite old movie and sit and iron stacks of fat quarters, strips yards of fabric. you may just find it can be very theraputic and you really start getting a real (feel) for your fabrics.

Thanks all of you for the answers to my question. You are great gals....