AS in RN vs. BS in RN

Hi, I'm a starting freshman @ LCC, doing my pre-req's and co-req's. I've read the some threads here and at forumshawaii.net...so just to clarify, there isn't much difference in the pay level of a staff nurse if they're 2yr. RN or 4yr. RN?...however, if you wanted to get a higher position than a staff nurse, you'd need a BS?
And wouldn't you have a greater chance of getting hired if you had a BS?
Or would it be better to spend those 2 extra years working at a CNA or LPN job so that you can earn money while getting your foot in the door for the RN job?
Thanks!