Hi, glad you decided to join us. You can use either type of needle, I think the circulars (with the cord) are easier to learn with because you don't have to balance the stick as you're trying to wrap the yarn around it and learning the sts. And they're a lot more versatile later on - many of us don't use straight ones anymore because you can use them just like straights as well as 'knitting in the round' which makes a seamless tube, like for sweaters, hats, mittens, etc.
If the cords stay coiled up, dip them (just the cords) in hot water for a minute or two, then hold them straight while they cool. That will help then the weight of the knitting will unkink them more.