So it turns out that the sewing machine works best if you have the presser foot DOWN and the feed dogs UP. Who'd've thunk it? I've been successfully sewing semi-straight lines on scrap fabric today. The zigzag stitch makes me happy.
This foray into sewing has led to a revelation: learning to knit changed the way I learn everything. It wasn't until my third attempt that I was able to figure it out. What made the difference was stick-to-it-tiveness. I really, really, really wanted to knit. Once I decided to do it, it wasn't even about the process or the finished product or anything besides not getting beaten by this stupid needlework that four-year-old Scandinavian children can do in their SLEEP.
And man, did I make mistakes. It probably took about 200 attempts before I was able to knit a full row -- and that's with dropped stitches, accidental YOs, and whatnot. But I once it clicked, it really clicked. It was the same with crochet. And I'm hoping it's the same with sewing.
So I'm keeping all this in mind as I slowly figure out the sewing machine on my kitchen table. It still sort of blows my mind that I will be stitching together pattern pieces, instead of creating the fabric, loop by loop. What a crazy shortcut to a finished garment!