I got lessons from a Vietnamese friend. I think her trick was that she cut the wrappers into a sort of cross shape rather than trying to burrito roll them. She cut the end off the square and laid it across the larger part, then folded it in for the ends, then rolled the wider part. I was using the wrong wrappers as well, trying for rice paper (which is for summer rolls, not fried), or the ones I can buy at my grocery store (Chinese-style, too heavy). The oil used didn't make much difference. The day she made them at my house I'd thought I had peanut oil on hand and wound up combining vegetable, canola and some other kind of oil another neighbor brought over so we'd have enough. They weren't deep fried, but were cooked in a generous amount (NOT sauteed), a good half-inch so that about half the roll is in the oil. When I did them on my own I used peanut oil and there was no discernible difference. I can't get the right wrappers around here, woe is me.