The Muslin you picked would be great to get started and I agree with RedGarnet222 - definitely wash and press the fabric before you start stitching.
I use just a regular thin embroidery needle and because I cross-stitch as well, I use DMC floss. Its colorfast so it doesn't bleed, has beautiful colors and I don't have to have a separate storage box for just embroidery thread and cross-stitch thread.