newbie question

[eyemhungry]

Hi everybody! I'm new here and I am currently teaching myself how to knit. So far, I am handling it ok. The videos on this site help so much! Anyway, the question... I am trying to figure out how you know what yarns are good and which ones are not. Right now, I am making my very first project (a baby blanket) as a test run. I am using yarn I found for cheap at Walmart. It's really a test run because I want to make the same blanket for a friend of mine's future baby. Long story short, I was just wondering what a good yarn would be for a baby blanket and any tips on how to know what I should get for projects? Thanks!