Is there a difference?

[Nocturna]

Hey everyone! Long time no talk

I'm on Knitpicks right now checking out the yarn for Christmas projects, and since I'm on a tight budget, I'm especially looking at the $1.99 yarn (Wool of the Andes and Telemark, in particular). Is there a difference between them? I mean I know they are made of different materials, but if I was to make a scarf or a hat, would one be better than the other?

Another question: If I were making a striped scarf, would it be ok to knit together, say, Wool of the Andes and Shine, which is mostly made of cotton?

Thanks for any help!!!