I would first sort your fabric into groups. Then when you see how much of each you have, you'll have a better knowledge of what to put that pile in: a covered plastic box, on a shelf folded in a pile, in a drawer, etc.
I have my fabric sorted into colors. I also have plastic covered boxes of multi - brights, multi-darks, OBW fabrics, as well as boxes of each color: blue, teal/turquiose, red, pink, etc. I've also batting pieces with a slip of paper pinned on the corner w/ it's measurements, in it's own big box also. Another big box has muslin pieces in it, with the same scrap of paper pinned on the corner (if it's a large piece). i have all my fabric in transparent boxes, with a label on the side and on the top edge of the cover. This is so when they are stacked on top of each other I can easily see what color is where. If you will be stacking storage boxes, it's helpful to have the same brand - they fit together better, but this isn't absolutely necessary. Mine aren't.
Organizing a roomful of fabric, yarn, craft supplies is a daunting task. Take it slow and you'll get there.
So sorry for the passing of your Mom. :(