Don't worry, dora, you'll get it! It took me a while to learn to purl as well. I found the book "The Complete Idiot's Guide to Knitting & Crochet" very helpful. Just remember to start with the yarn in front of your work. Oh, and always ask a lot of questions! This is the nicest forum ever
As far as garter-stitch scarves go, have you seen scribble lace
before? This particular pattern calls for stockinette stitch, but garter stitch will work fine. Another option would be using a fine yarn on big needles to make a wispy sort of scarf, or you could knit on the bias (make a slanted scarf by increasing at one end and decreasing at the other).