I prefer anything from Quilter's Dream. The kind of batting depends on the way it will be quilted and used. For example: a baby quilt will be washed a lot--I prefer a poly or poly blend for these (or the Dream Angel, which is flame-retardant). Poly has no memory, so it is good for wall quilts or quilts that will be folded up then re-hung. Good old-fashioned cotton is great if you want 'snuggly'.
Hand quilting? Then, you will want to choose a poly (lo-loft) or a wool batting. These are easier to needle.
There are so many things to consider when choosing your batting. Remember to read the package of the batting you are using for instructions on laundering and how densely your quilt needs to be quilted for optimum results.