I would say DEFINITELY go with the 4-year/bachelors plan and here's how you ought to do it:
If NIU is your choice then perhaps set up an appointment with them first. Find out some information about how credits/courses transfer to their institution. Ask things like "If I was planning on taking some courses at a community college and then enrolling at your school as an elem ed major, what would you suggest? How many years are transfer credits good (in other words, if you take a class now at the community college and then want to transfer it over, they might only accept credit taken with the last 5 years).
Then, spend a few years taking the necessary and pre-requisite courses at a community college. Get a catalog from NIU and read through what classes are needed for a bachelors degree. Take the 'general education' requirements like psychology, math, bio/chem, English/writing, phys. ed. - all the stuff that you 'have' to take but are not major requirements. Why do it this way? Well, at a community college the classes are a HECK of a lot cheaper and might possibly be easier. Get the 'required' stuff out of the way so that when you get to NIU you can concentrate on your elem ed major courses. You should also set up an appointment with someone at the community college where you are planning on attending so they can help you negotiate the process as well.
Keep in mind that several community colleges cater to non-traditional students. This means that they often have flexible learning options, such as evening/weekend class choices, online or distance learning, or other options which could decrease your need for childcare.
Personally, I think you may wish to consider skipping getting an AA in ECE. Why? People with degrees in ECE typically can ONLY get certified by the state to teach in a daycare, preschool, or kindergarten. If you're not wanting to go that route, why waste your money and your time on that when you can be knocking out classes you *have* to take (eventually) for a 4-year/bachelors in elementary education? And yes, you are 100% correct in thinking that you have much better options with a BS in Elem Ed.
To sum it up:
-Take your general education requirements at the community college.
-Transfer those to NIU so you don't waste 2 years and a lot of money on stuff you can take 'on the cheap' at the CC.
-Focus on your elem ed stuff (and anything else you might need) at NIU.
-Make appointments with both the CC and NIU to make sure this would work.
-Also check the Illinois State Board of Education website to see what is needed for certification (www.isbe.state.il.us) ALTHOUGH understand their website is not terribly user-friendly.
Good luck to you and feel free to e-mail me with any questions you might have. I'm currently teaching high school, but in my former professional life I was an admissions counselor at a university.