For machine quilting I use either Gutermann 100% cotton, Mettler silk finish cotton, or (my favorite) Star machine quilting and craft 100% Egyptian cotton thread. The Star thread comes on a 1200 yard spool and is made by Coats and Clark. You can find it at Walmart sometimes, some quilt shops, JoAnns or Hancock Fabrics. It is either solid or variegated. You can find out more info about it at http://www.starthreads.com/products.htm Online you can buy it at Keepsake Quilting.
I do not hand quilt-cannot help you there!!