We recently got our sewing machine out of the understairs cupboard, it hadn't been used for aout 20 years, so when we tried to sew, it would have none of it. We put it in for a full service, and now it is like a new one.......I guess what Im trying to say is, get it serviced so you know you are working from a known good point, because you can spend many frustrating hours with a machine that looks OK, but isn't. Another really useful tip is to use good quality thread, the stuff from the poundshop will generally snag and mess you around. The machines can sometimes take a bit of setting up, but on done run like a, well, sewing machine!!.....
Paul