"Question what are good colors to have in your stash? I know it is up to me but I'm sure there are some staples that are needed."
I would shop with a particular quilt in mind. I have a "wish" list of quilts or a color scheme in mind when I go shopping. If you don't have a plan you will end up with a lot of hard to use fabrics. Backgrounds are always good to buy but don't limit yourself to white or off white, black makes a great background too!!
If you love it buy at least 3 yards and watch out ... we mostly all buy too many mediums and not enough dark darks and light lights or those accents that make a quilt sing.
Welcome to the quilting world!!
cindy