Hi Sammijo and welcome to the board. You've got a lot of questions packed in there! I think I can answer at least one. If by a "blue sized needle" you mean a jeans needle, then yes that would work. To verify this, you really need to post the needle size number. It's printed on the needle (in teeny tiny text) or it's on the package (much easier to see!). As far as the stitch length, I usually lengthen it to at least 3, but it's personal preference. You will want to do a practice sandwich first. Try a couple lengths and see what you and your machine like.